diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index ace3d5ee8cfe2..78df7551bf881 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -9370,25 +9370,6 @@ namespace ts {
             return type.resolvedProperties;
         }
 
-        function getPossiblePropertiesOfUnionType(type: UnionType): Symbol[] {
-            if (type.possiblePropertyCache) {
-                return type.possiblePropertyCache.size ? arrayFrom(type.possiblePropertyCache.values()) : emptyArray;
-            }
-            type.possiblePropertyCache = createSymbolTable();
-            for (const t of type.types) {
-                for (const p of getPropertiesOfType(t)) {
-                    if (!type.possiblePropertyCache.has(p.escapedName)) {
-                        const prop = getUnionOrIntersectionProperty(type, p.escapedName);
-                        if (prop) {
-                            type.possiblePropertyCache.set(p.escapedName, prop);
-                        }
-                    }
-                }
-            }
-            // We can't simply use the normal property cache here, since that will contain cached apparent type members :(
-            return type.possiblePropertyCache.size ? arrayFrom(type.possiblePropertyCache.values()) : emptyArray;
-        }
-
         function getPropertiesOfType(type: Type): Symbol[] {
             type = getApparentType(type);
             return type.flags & TypeFlags.UnionOrIntersection ?
@@ -14614,8 +14595,7 @@ namespace ts {
                 const isComparingJsxAttributes = !!(getObjectFlags(source) & ObjectFlags.JsxAttributes);
                 const isPerformingExcessPropertyChecks = !isApparentIntersectionConstituent && (isObjectLiteralType(source) && getObjectFlags(source) & ObjectFlags.FreshLiteral);
                 if (isPerformingExcessPropertyChecks) {
-                    const discriminantType = target.flags & TypeFlags.Union ? findMatchingDiscriminantType(source, target as UnionType) : undefined;
-                    if (hasExcessProperties(<FreshObjectLiteralType>source, target, discriminantType, reportErrors)) {
+                    if (hasExcessProperties(<FreshObjectLiteralType>source, target, reportErrors)) {
                         if (reportErrors) {
                             reportRelationError(headMessage, source, target);
                         }
@@ -14657,13 +14637,6 @@ namespace ts {
                 else {
                     if (target.flags & TypeFlags.Union) {
                         result = typeRelatedToSomeType(getRegularTypeOfObjectLiteral(source), <UnionType>target, reportErrors && !(source.flags & TypeFlags.Primitive) && !(target.flags & TypeFlags.Primitive));
-                        if (result && (isPerformingExcessPropertyChecks || isPerformingCommonPropertyChecks)) {
-                            // Validate against excess props using the original `source`
-                            const discriminantType = findMatchingDiscriminantType(source, target as UnionType) || filterPrimitivesIfContainsNonPrimitive(target as UnionType);
-                            if (!propertiesRelatedTo(source, discriminantType, reportErrors, /*excludedProperties*/ undefined, isIntersectionConstituent)) {
-                                return Ternary.False;
-                            }
-                        }
                     }
                     else if (target.flags & TypeFlags.Intersection) {
                         isIntersectionConstituent = true; // set here to affect the following trio of checks
@@ -14776,26 +14749,38 @@ namespace ts {
                 return Ternary.False;
             }
 
-            function hasExcessProperties(source: FreshObjectLiteralType, target: Type, discriminant: Type | undefined, reportErrors: boolean): boolean {
-                if (!noImplicitAny && getObjectFlags(target) & ObjectFlags.JSLiteral) {
+            function getTypeOfPropertyInTypes(types: Type[], name: __String) {
+                const appendPropType = (propTypes: Type[] | undefined, type: Type) => {
+                    type = getApparentType(type);
+                    const prop = type.flags & TypeFlags.UnionOrIntersection ? getPropertyOfUnionOrIntersectionType(<UnionOrIntersectionType>type, name) : getPropertyOfObjectType(type, name);
+                    const propType = prop && getTypeOfSymbol(prop) || isNumericLiteralName(name) && getIndexTypeOfType(type, IndexKind.Number) || getIndexTypeOfType(type, IndexKind.String) || undefinedType;
+                    return append(propTypes, propType);
+                };
+                return getUnionType(reduceLeft(types, appendPropType, /*initial*/ undefined) || emptyArray);
+            }
+
+            function hasExcessProperties(source: FreshObjectLiteralType, target: Type, reportErrors: boolean): boolean {
+                if (!isExcessPropertyCheckTarget(target) || !noImplicitAny && getObjectFlags(target) & ObjectFlags.JSLiteral) {
                     return false; // Disable excess property checks on JS literals to simulate having an implicit "index signature" - but only outside of noImplicitAny
                 }
-                if (isExcessPropertyCheckTarget(target)) {
-                    const isComparingJsxAttributes = !!(getObjectFlags(source) & ObjectFlags.JsxAttributes);
-                    if ((relation === assignableRelation || relation === comparableRelation) &&
-                        (isTypeSubsetOf(globalObjectType, target) || (!isComparingJsxAttributes && isEmptyObjectType(target)))) {
-                        return false;
-                    }
-                    if (discriminant) {
-                        // check excess properties against discriminant type only, not the entire union
-                        return hasExcessProperties(source, discriminant, /*discriminant*/ undefined, reportErrors);
-                    }
-                    for (const prop of getPropertiesOfType(source)) {
-                        if (shouldCheckAsExcessProperty(prop, source.symbol) && !isKnownProperty(target, prop.escapedName, isComparingJsxAttributes)) {
+                const isComparingJsxAttributes = !!(getObjectFlags(source) & ObjectFlags.JsxAttributes);
+                if ((relation === assignableRelation || relation === comparableRelation) &&
+                    (isTypeSubsetOf(globalObjectType, target) || (!isComparingJsxAttributes && isEmptyObjectType(target)))) {
+                    return false;
+                }
+                let reducedTarget = target;
+                let checkTypes: Type[] | undefined;
+                if (target.flags & TypeFlags.Union) {
+                    reducedTarget = findMatchingDiscriminantType(source, <UnionType>target) || filterPrimitivesIfContainsNonPrimitive(<UnionType>target);
+                    checkTypes = reducedTarget.flags & TypeFlags.Union ? (<UnionType>reducedTarget).types : [reducedTarget];
+                }
+                for (const prop of getPropertiesOfType(source)) {
+                    if (shouldCheckAsExcessProperty(prop, source.symbol)) {
+                        if (!isKnownProperty(reducedTarget, prop.escapedName, isComparingJsxAttributes)) {
                             if (reportErrors) {
                                 // Report error in terms of object types in the target as those are the only ones
                                 // we check in isKnownProperty.
-                                const errorTarget = filterType(target, isExcessPropertyCheckTarget);
+                                const errorTarget = filterType(reducedTarget, isExcessPropertyCheckTarget);
                                 // We know *exactly* where things went wrong when comparing the types.
                                 // Use this property as the error node as this will be more helpful in
                                 // reasoning about what went wrong.
@@ -14826,7 +14811,6 @@ namespace ts {
                                             suggestion = getSuggestionForNonexistentProperty(name, errorTarget);
                                         }
                                     }
-
                                     if (suggestion !== undefined) {
                                         reportError(Diagnostics.Object_literal_may_only_specify_known_properties_but_0_does_not_exist_in_type_1_Did_you_mean_to_write_2,
                                             symbolToString(prop), typeToString(errorTarget), suggestion);
@@ -14839,6 +14823,12 @@ namespace ts {
                             }
                             return true;
                         }
+                        if (checkTypes && !isRelatedTo(getTypeOfSymbol(prop), getTypeOfPropertyInTypes(checkTypes, prop.escapedName), reportErrors)) {
+                            if (reportErrors) {
+                                reportIncompatibleError(Diagnostics.Types_of_property_0_are_incompatible, symbolToString(prop));
+                            }
+                            return true;
+                        }
                     }
                 }
                 return false;
@@ -15839,7 +15829,7 @@ namespace ts {
                 }
                 // We only call this for union target types when we're attempting to do excess property checking - in those cases, we want to get _all possible props_
                 // from the target union, across all members
-                const properties = target.flags & TypeFlags.Union ? getPossiblePropertiesOfUnionType(target as UnionType) : getPropertiesOfType(target);
+                const properties = getPropertiesOfType(target);
                 const numericNamesOnly = isTupleType(source) && isTupleType(target);
                 for (const targetProp of excludeProperties(properties, excludedProperties)) {
                     const name = targetProp.escapedName;
@@ -17344,7 +17334,7 @@ namespace ts {
         }
 
         function* getUnmatchedProperties(source: Type, target: Type, requireOptionalProperties: boolean, matchDiscriminantProperties: boolean): IterableIterator<Symbol> {
-            const properties = target.flags & TypeFlags.Union ? getPossiblePropertiesOfUnionType(target as UnionType) : getPropertiesOfType(target);
+            const properties = getPropertiesOfType(target);
             for (const targetProp of properties) {
                 if (requireOptionalProperties || !(targetProp.flags & SymbolFlags.Optional || getCheckFlags(targetProp) & CheckFlags.Partial)) {
                     const sourceProp = getPropertyOfType(source, targetProp.escapedName);
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index 08cc7343ccaea..4c33bf68b4b48 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -4483,8 +4483,6 @@ namespace ts {
     }
 
     export interface UnionType extends UnionOrIntersectionType {
-        /* @internal */
-        possiblePropertyCache?: SymbolTable;       // Cache of _all_ resolved properties less any from aparent members
     }
 
     export interface IntersectionType extends UnionOrIntersectionType {
diff --git a/tests/baselines/reference/deepExcessPropertyCheckingWhenTargetIsIntersection.errors.txt b/tests/baselines/reference/deepExcessPropertyCheckingWhenTargetIsIntersection.errors.txt
index 1f2552d47f271..975f2a37d3863 100644
--- a/tests/baselines/reference/deepExcessPropertyCheckingWhenTargetIsIntersection.errors.txt
+++ b/tests/baselines/reference/deepExcessPropertyCheckingWhenTargetIsIntersection.errors.txt
@@ -1,8 +1,9 @@
 tests/cases/compiler/deepExcessPropertyCheckingWhenTargetIsIntersection.ts(21,33): error TS2322: Type '{ INVALID_PROP_NAME: string; ariaLabel: string; }' is not assignable to type 'ITestProps'.
   Object literal may only specify known properties, and 'INVALID_PROP_NAME' does not exist in type 'ITestProps'.
-tests/cases/compiler/deepExcessPropertyCheckingWhenTargetIsIntersection.ts(27,34): error TS2200: The types of 'icon.props' are incompatible between these types.
-  Type '{ INVALID_PROP_NAME: string; ariaLabel: string; }' is not assignable to type 'ITestProps'.
-    Object literal may only specify known properties, and 'INVALID_PROP_NAME' does not exist in type 'ITestProps'.
+tests/cases/compiler/deepExcessPropertyCheckingWhenTargetIsIntersection.ts(27,34): error TS2345: Argument of type '{ icon: { props: { INVALID_PROP_NAME: string; ariaLabel: string; }; }; }' is not assignable to parameter of type '(TestProps & { children?: number; }) | ({ props2: { x: number; }; } & { children?: number; })'.
+  The types of 'icon.props' are incompatible between these types.
+    Type '{ INVALID_PROP_NAME: string; ariaLabel: string; }' is not assignable to type 'ITestProps'.
+      Object literal may only specify known properties, and 'INVALID_PROP_NAME' does not exist in type 'ITestProps'.
 
 
 ==== tests/cases/compiler/deepExcessPropertyCheckingWhenTargetIsIntersection.ts (2 errors) ====
@@ -38,7 +39,8 @@ tests/cases/compiler/deepExcessPropertyCheckingWhenTargetIsIntersection.ts(27,34
     
     TestComponent2({icon: { props: { INVALID_PROP_NAME: 'share', ariaLabel: 'test label' } }});
                                      ~~~~~~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2200: The types of 'icon.props' are incompatible between these types.
-!!! error TS2200:   Type '{ INVALID_PROP_NAME: string; ariaLabel: string; }' is not assignable to type 'ITestProps'.
-!!! error TS2200:     Object literal may only specify known properties, and 'INVALID_PROP_NAME' does not exist in type 'ITestProps'.
+!!! error TS2345: Argument of type '{ icon: { props: { INVALID_PROP_NAME: string; ariaLabel: string; }; }; }' is not assignable to parameter of type '(TestProps & { children?: number; }) | ({ props2: { x: number; }; } & { children?: number; })'.
+!!! error TS2345:   The types of 'icon.props' are incompatible between these types.
+!!! error TS2345:     Type '{ INVALID_PROP_NAME: string; ariaLabel: string; }' is not assignable to type 'ITestProps'.
+!!! error TS2345:       Object literal may only specify known properties, and 'INVALID_PROP_NAME' does not exist in type 'ITestProps'.
     
\ No newline at end of file
diff --git a/tests/baselines/reference/discriminateObjectTypesOnly.errors.txt b/tests/baselines/reference/discriminateObjectTypesOnly.errors.txt
deleted file mode 100644
index efe5bf4ccedb2..0000000000000
--- a/tests/baselines/reference/discriminateObjectTypesOnly.errors.txt
+++ /dev/null
@@ -1,17 +0,0 @@
-tests/cases/compiler/discriminateObjectTypesOnly.ts(9,7): error TS2741: Property 'toFixed' is missing in type '{ toString: undefined; }' but required in type '{ toFixed: null; toString: undefined; }'.
-
-
-==== tests/cases/compiler/discriminateObjectTypesOnly.ts (1 errors) ====
-    type Thing = number | object;
-    const k: Thing = { toFixed: null }; // OK, satisfies object
-    
-    type Thing2 = number | { toFixed: null } | object;
-    const q: Thing2 = { toFixed: null };
-    const h: Thing2 = { toString: null }; // OK, satisfies object
-    
-    type Thing3 = number | { toFixed: null, toString: undefined } | object;
-    const l: Thing3 = { toString: undefined }; // error, toFixed isn't null
-          ~
-!!! error TS2741: Property 'toFixed' is missing in type '{ toString: undefined; }' but required in type '{ toFixed: null; toString: undefined; }'.
-!!! related TS2728 tests/cases/compiler/discriminateObjectTypesOnly.ts:8:26: 'toFixed' is declared here.
-    
\ No newline at end of file
diff --git a/tests/baselines/reference/errorsOnUnionsOfOverlappingObjects01.errors.txt b/tests/baselines/reference/errorsOnUnionsOfOverlappingObjects01.errors.txt
index 1b8dab19b5b41..38ae9542a4060 100644
--- a/tests/baselines/reference/errorsOnUnionsOfOverlappingObjects01.errors.txt
+++ b/tests/baselines/reference/errorsOnUnionsOfOverlappingObjects01.errors.txt
@@ -3,9 +3,8 @@ tests/cases/compiler/errorsOnUnionsOfOverlappingObjects01.ts(18,3): error TS2345
     Types of property 'b' are incompatible.
       Type 'string' is not assignable to type 'number'.
 tests/cases/compiler/errorsOnUnionsOfOverlappingObjects01.ts(19,3): error TS2345: Argument of type '{ a: string; b: string; }' is not assignable to parameter of type 'Foo | Other'.
-  Type '{ a: string; b: string; }' is not assignable to type 'Foo'.
-    Types of property 'b' are incompatible.
-      Type 'string' is not assignable to type 'number'.
+  Types of property 'b' are incompatible.
+    Type 'string' is not assignable to type 'number'.
 tests/cases/compiler/errorsOnUnionsOfOverlappingObjects01.ts(24,5): error TS2345: Argument of type '{ a: string; b: string; }' is not assignable to parameter of type 'Bar | Other'.
   Object literal may only specify known properties, and 'a' does not exist in type 'Bar | Other'.
 tests/cases/compiler/errorsOnUnionsOfOverlappingObjects01.ts(42,10): error TS2345: Argument of type '{ dog: string; }' is not assignable to parameter of type 'ExoticAnimal'.
@@ -45,9 +44,8 @@ tests/cases/compiler/errorsOnUnionsOfOverlappingObjects01.ts(47,10): error TS234
     f({ a: '', b: '' })
       ~~~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ a: string; b: string; }' is not assignable to parameter of type 'Foo | Other'.
-!!! error TS2345:   Type '{ a: string; b: string; }' is not assignable to type 'Foo'.
-!!! error TS2345:     Types of property 'b' are incompatible.
-!!! error TS2345:       Type 'string' is not assignable to type 'number'.
+!!! error TS2345:   Types of property 'b' are incompatible.
+!!! error TS2345:     Type 'string' is not assignable to type 'number'.
     
     declare function g(x: Bar | Other): any;
     
diff --git a/tests/baselines/reference/excessPropertyCheckWithUnions.errors.txt b/tests/baselines/reference/excessPropertyCheckWithUnions.errors.txt
index 72da324caf759..0d56383ed9a2f 100644
--- a/tests/baselines/reference/excessPropertyCheckWithUnions.errors.txt
+++ b/tests/baselines/reference/excessPropertyCheckWithUnions.errors.txt
@@ -20,14 +20,24 @@ tests/cases/compiler/excessPropertyCheckWithUnions.ts(49,35): error TS2322: Type
   Object literal may only specify known properties, and 'second' does not exist in type '{ a: 1; b: 1; first: string; }'.
 tests/cases/compiler/excessPropertyCheckWithUnions.ts(50,35): error TS2322: Type '{ a: 1; b: 1; first: string; third: string; }' is not assignable to type 'Overlapping'.
   Object literal may only specify known properties, and 'third' does not exist in type '{ a: 1; b: 1; first: string; }'.
-tests/cases/compiler/excessPropertyCheckWithUnions.ts(66,9): error TS2326: Types of property 'n' are incompatible.
-  Type '{ a: string; b: string; }' is not assignable to type 'AN'.
-    Object literal may only specify known properties, and 'b' does not exist in type 'AN'.
+tests/cases/compiler/excessPropertyCheckWithUnions.ts(66,9): error TS2322: Type '{ kind: "A"; n: { a: string; b: string; }; }' is not assignable to type 'AB'.
+  Types of property 'n' are incompatible.
+    Type '{ a: string; b: string; }' is not assignable to type 'AN'.
+      Object literal may only specify known properties, and 'b' does not exist in type 'AN'.
 tests/cases/compiler/excessPropertyCheckWithUnions.ts(87,5): error TS2322: Type '{ tag: "button"; type: "submit"; href: string; }' is not assignable to type 'Union'.
   Object literal may only specify known properties, and 'href' does not exist in type 'Button'.
+tests/cases/compiler/excessPropertyCheckWithUnions.ts(107,7): error TS2322: Type '{ foo: string; }' is not assignable to type 'ObjectDataSpecification'.
+  Types of property 'foo' are incompatible.
+    Type 'string' is not assignable to type 'IValue | undefined'.
+tests/cases/compiler/excessPropertyCheckWithUnions.ts(113,7): error TS2322: Type '{ a: string; }' is not assignable to type '{ [x: string]: number; } | { [x: number]: number; }'.
+  Types of property 'a' are incompatible.
+    Type 'string' is not assignable to type 'number | undefined'.
+tests/cases/compiler/excessPropertyCheckWithUnions.ts(114,7): error TS2322: Type '{ a: number; c: string; }' is not assignable to type '{ [x: string]: number; } | { a: number; }'.
+  Types of property 'c' are incompatible.
+    Type 'string' is not assignable to type 'number | undefined'.
 
 
-==== tests/cases/compiler/excessPropertyCheckWithUnions.ts (11 errors) ====
+==== tests/cases/compiler/excessPropertyCheckWithUnions.ts (14 errors) ====
     type ADT = {
         tag: "A",
         a1: string
@@ -127,9 +137,10 @@ tests/cases/compiler/excessPropertyCheckWithUnions.ts(87,5): error TS2322: Type
             a: "a",
             b: "b", // excess -- kind: "A"
             ~~~~~~
-!!! error TS2326: Types of property 'n' are incompatible.
-!!! error TS2326:   Type '{ a: string; b: string; }' is not assignable to type 'AN'.
-!!! error TS2326:     Object literal may only specify known properties, and 'b' does not exist in type 'AN'.
+!!! error TS2322: Type '{ kind: "A"; n: { a: string; b: string; }; }' is not assignable to type 'AB'.
+!!! error TS2322:   Types of property 'n' are incompatible.
+!!! error TS2322:     Type '{ a: string; b: string; }' is not assignable to type 'AN'.
+!!! error TS2322:       Object literal may only specify known properties, and 'b' does not exist in type 'AN'.
         }
     }
     const abac: AB = {
@@ -155,4 +166,42 @@ tests/cases/compiler/excessPropertyCheckWithUnions.ts(87,5): error TS2322: Type
 !!! error TS2322: Type '{ tag: "button"; type: "submit"; href: string; }' is not assignable to type 'Union'.
 !!! error TS2322:   Object literal may only specify known properties, and 'href' does not exist in type 'Button'.
     };
+    
+    // Repro from #34611
+    
+    interface IValue {
+      value: string
+    }
+    
+    interface StringKeys { 
+        [propertyName: string]: IValue;
+    };
+    
+    interface NumberKeys {
+        [propertyName: number]: IValue;
+    }
+    
+    type ObjectDataSpecification = StringKeys | NumberKeys;
+    
+    
+    const dataSpecification: ObjectDataSpecification = {  // Error
+          ~~~~~~~~~~~~~~~~~
+!!! error TS2322: Type '{ foo: string; }' is not assignable to type 'ObjectDataSpecification'.
+!!! error TS2322:   Types of property 'foo' are incompatible.
+!!! error TS2322:     Type 'string' is not assignable to type 'IValue | undefined'.
+        foo: "asdfsadffsd"
+    };
+    
+    // Repro from #34611
+    
+    const obj1: { [x: string]: number } | { [x: number]: number } = { a: 'abc' };  // Error
+          ~~~~
+!!! error TS2322: Type '{ a: string; }' is not assignable to type '{ [x: string]: number; } | { [x: number]: number; }'.
+!!! error TS2322:   Types of property 'a' are incompatible.
+!!! error TS2322:     Type 'string' is not assignable to type 'number | undefined'.
+    const obj2: { [x: string]: number } | { a: number } = { a: 5, c: 'abc' };  // Error
+          ~~~~
+!!! error TS2322: Type '{ a: number; c: string; }' is not assignable to type '{ [x: string]: number; } | { a: number; }'.
+!!! error TS2322:   Types of property 'c' are incompatible.
+!!! error TS2322:     Type 'string' is not assignable to type 'number | undefined'.
     
\ No newline at end of file
diff --git a/tests/baselines/reference/excessPropertyCheckWithUnions.js b/tests/baselines/reference/excessPropertyCheckWithUnions.js
index 691a64f65b808..34cd337705a34 100644
--- a/tests/baselines/reference/excessPropertyCheckWithUnions.js
+++ b/tests/baselines/reference/excessPropertyCheckWithUnions.js
@@ -87,6 +87,32 @@ const obj: Union = {
     // should have error here
     href: 'foo',
 };
+
+// Repro from #34611
+
+interface IValue {
+  value: string
+}
+
+interface StringKeys { 
+    [propertyName: string]: IValue;
+};
+
+interface NumberKeys {
+    [propertyName: number]: IValue;
+}
+
+type ObjectDataSpecification = StringKeys | NumberKeys;
+
+
+const dataSpecification: ObjectDataSpecification = {  // Error
+    foo: "asdfsadffsd"
+};
+
+// Repro from #34611
+
+const obj1: { [x: string]: number } | { [x: number]: number } = { a: 'abc' };  // Error
+const obj2: { [x: string]: number } | { a: number } = { a: 5, c: 'abc' };  // Error
 
 
 //// [excessPropertyCheckWithUnions.js]
@@ -144,3 +170,10 @@ var obj = {
     // should have error here
     href: 'foo'
 };
+;
+var dataSpecification = {
+    foo: "asdfsadffsd"
+};
+// Repro from #34611
+var obj1 = { a: 'abc' }; // Error
+var obj2 = { a: 5, c: 'abc' }; // Error
diff --git a/tests/baselines/reference/excessPropertyCheckWithUnions.symbols b/tests/baselines/reference/excessPropertyCheckWithUnions.symbols
index 749e359d4a1cc..8fb86125a5731 100644
--- a/tests/baselines/reference/excessPropertyCheckWithUnions.symbols
+++ b/tests/baselines/reference/excessPropertyCheckWithUnions.symbols
@@ -254,3 +254,59 @@ const obj: Union = {
 
 };
 
+// Repro from #34611
+
+interface IValue {
+>IValue : Symbol(IValue, Decl(excessPropertyCheckWithUnions.ts, 87, 2))
+
+  value: string
+>value : Symbol(IValue.value, Decl(excessPropertyCheckWithUnions.ts, 91, 18))
+}
+
+interface StringKeys { 
+>StringKeys : Symbol(StringKeys, Decl(excessPropertyCheckWithUnions.ts, 93, 1))
+
+    [propertyName: string]: IValue;
+>propertyName : Symbol(propertyName, Decl(excessPropertyCheckWithUnions.ts, 96, 5))
+>IValue : Symbol(IValue, Decl(excessPropertyCheckWithUnions.ts, 87, 2))
+
+};
+
+interface NumberKeys {
+>NumberKeys : Symbol(NumberKeys, Decl(excessPropertyCheckWithUnions.ts, 97, 2))
+
+    [propertyName: number]: IValue;
+>propertyName : Symbol(propertyName, Decl(excessPropertyCheckWithUnions.ts, 100, 5))
+>IValue : Symbol(IValue, Decl(excessPropertyCheckWithUnions.ts, 87, 2))
+}
+
+type ObjectDataSpecification = StringKeys | NumberKeys;
+>ObjectDataSpecification : Symbol(ObjectDataSpecification, Decl(excessPropertyCheckWithUnions.ts, 101, 1))
+>StringKeys : Symbol(StringKeys, Decl(excessPropertyCheckWithUnions.ts, 93, 1))
+>NumberKeys : Symbol(NumberKeys, Decl(excessPropertyCheckWithUnions.ts, 97, 2))
+
+
+const dataSpecification: ObjectDataSpecification = {  // Error
+>dataSpecification : Symbol(dataSpecification, Decl(excessPropertyCheckWithUnions.ts, 106, 5))
+>ObjectDataSpecification : Symbol(ObjectDataSpecification, Decl(excessPropertyCheckWithUnions.ts, 101, 1))
+
+    foo: "asdfsadffsd"
+>foo : Symbol(foo, Decl(excessPropertyCheckWithUnions.ts, 106, 52))
+
+};
+
+// Repro from #34611
+
+const obj1: { [x: string]: number } | { [x: number]: number } = { a: 'abc' };  // Error
+>obj1 : Symbol(obj1, Decl(excessPropertyCheckWithUnions.ts, 112, 5))
+>x : Symbol(x, Decl(excessPropertyCheckWithUnions.ts, 112, 15))
+>x : Symbol(x, Decl(excessPropertyCheckWithUnions.ts, 112, 41))
+>a : Symbol(a, Decl(excessPropertyCheckWithUnions.ts, 112, 65))
+
+const obj2: { [x: string]: number } | { a: number } = { a: 5, c: 'abc' };  // Error
+>obj2 : Symbol(obj2, Decl(excessPropertyCheckWithUnions.ts, 113, 5))
+>x : Symbol(x, Decl(excessPropertyCheckWithUnions.ts, 113, 15))
+>a : Symbol(a, Decl(excessPropertyCheckWithUnions.ts, 113, 39))
+>a : Symbol(a, Decl(excessPropertyCheckWithUnions.ts, 113, 55))
+>c : Symbol(c, Decl(excessPropertyCheckWithUnions.ts, 113, 61))
+
diff --git a/tests/baselines/reference/excessPropertyCheckWithUnions.types b/tests/baselines/reference/excessPropertyCheckWithUnions.types
index f56aa287daa7e..38e9a6c81e7a4 100644
--- a/tests/baselines/reference/excessPropertyCheckWithUnions.types
+++ b/tests/baselines/reference/excessPropertyCheckWithUnions.types
@@ -312,3 +312,55 @@ const obj: Union = {
 
 };
 
+// Repro from #34611
+
+interface IValue {
+  value: string
+>value : string
+}
+
+interface StringKeys { 
+    [propertyName: string]: IValue;
+>propertyName : string
+
+};
+
+interface NumberKeys {
+    [propertyName: number]: IValue;
+>propertyName : number
+}
+
+type ObjectDataSpecification = StringKeys | NumberKeys;
+>ObjectDataSpecification : ObjectDataSpecification
+
+
+const dataSpecification: ObjectDataSpecification = {  // Error
+>dataSpecification : ObjectDataSpecification
+>{  // Error    foo: "asdfsadffsd"} : { foo: string; }
+
+    foo: "asdfsadffsd"
+>foo : string
+>"asdfsadffsd" : "asdfsadffsd"
+
+};
+
+// Repro from #34611
+
+const obj1: { [x: string]: number } | { [x: number]: number } = { a: 'abc' };  // Error
+>obj1 : { [x: string]: number; } | { [x: number]: number; }
+>x : string
+>x : number
+>{ a: 'abc' } : { a: string; }
+>a : string
+>'abc' : "abc"
+
+const obj2: { [x: string]: number } | { a: number } = { a: 5, c: 'abc' };  // Error
+>obj2 : { [x: string]: number; } | { a: number; }
+>x : string
+>a : number
+>{ a: 5, c: 'abc' } : { a: number; c: string; }
+>a : number
+>5 : 5
+>c : string
+>'abc' : "abc"
+
diff --git a/tests/baselines/reference/mappedTypeIndexedAccess.errors.txt b/tests/baselines/reference/mappedTypeIndexedAccess.errors.txt
index 24eae941c61bd..070f48c216af7 100644
--- a/tests/baselines/reference/mappedTypeIndexedAccess.errors.txt
+++ b/tests/baselines/reference/mappedTypeIndexedAccess.errors.txt
@@ -1,11 +1,9 @@
 tests/cases/compiler/mappedTypeIndexedAccess.ts(18,5): error TS2322: Type '{ key: "foo"; value: number; }' is not assignable to type '{ key: "foo"; value: string; } | { key: "bar"; value: number; }'.
-  Type '{ key: "foo"; value: number; }' is not assignable to type '{ key: "foo"; value: string; }'.
-    Types of property 'value' are incompatible.
-      Type 'number' is not assignable to type 'string'.
+  Types of property 'value' are incompatible.
+    Type 'number' is not assignable to type 'string'.
 tests/cases/compiler/mappedTypeIndexedAccess.ts(24,5): error TS2322: Type '{ key: "foo"; value: number; }' is not assignable to type '{ key: "foo"; value: string; } | { key: "bar"; value: number; }'.
-  Type '{ key: "foo"; value: number; }' is not assignable to type '{ key: "foo"; value: string; }'.
-    Types of property 'value' are incompatible.
-      Type 'number' is not assignable to type 'string'.
+  Types of property 'value' are incompatible.
+    Type 'number' is not assignable to type 'string'.
 
 
 ==== tests/cases/compiler/mappedTypeIndexedAccess.ts (2 errors) ====
@@ -29,9 +27,8 @@ tests/cases/compiler/mappedTypeIndexedAccess.ts(24,5): error TS2322: Type '{ key
     let pair1: Pair<FooBar> = {
         ~~~~~
 !!! error TS2322: Type '{ key: "foo"; value: number; }' is not assignable to type '{ key: "foo"; value: string; } | { key: "bar"; value: number; }'.
-!!! error TS2322:   Type '{ key: "foo"; value: number; }' is not assignable to type '{ key: "foo"; value: string; }'.
-!!! error TS2322:     Types of property 'value' are incompatible.
-!!! error TS2322:       Type 'number' is not assignable to type 'string'.
+!!! error TS2322:   Types of property 'value' are incompatible.
+!!! error TS2322:     Type 'number' is not assignable to type 'string'.
         key: "foo",
         value: 3
     };
@@ -40,9 +37,8 @@ tests/cases/compiler/mappedTypeIndexedAccess.ts(24,5): error TS2322: Type '{ key
     let pair2: Pairs<FooBar>[keyof FooBar] = {
         ~~~~~
 !!! error TS2322: Type '{ key: "foo"; value: number; }' is not assignable to type '{ key: "foo"; value: string; } | { key: "bar"; value: number; }'.
-!!! error TS2322:   Type '{ key: "foo"; value: number; }' is not assignable to type '{ key: "foo"; value: string; }'.
-!!! error TS2322:     Types of property 'value' are incompatible.
-!!! error TS2322:       Type 'number' is not assignable to type 'string'.
+!!! error TS2322:   Types of property 'value' are incompatible.
+!!! error TS2322:     Type 'number' is not assignable to type 'string'.
         key: "foo",
         value: 3
     };
diff --git a/tests/baselines/reference/nonObjectUnionNestedExcessPropertyCheck.errors.txt b/tests/baselines/reference/nonObjectUnionNestedExcessPropertyCheck.errors.txt
index 4cf8a99e0eafb..55cc7ea4c91b6 100644
--- a/tests/baselines/reference/nonObjectUnionNestedExcessPropertyCheck.errors.txt
+++ b/tests/baselines/reference/nonObjectUnionNestedExcessPropertyCheck.errors.txt
@@ -1,12 +1,13 @@
 tests/cases/compiler/nonObjectUnionNestedExcessPropertyCheck.ts(13,35): error TS2322: Type '{ INVALID_PROP_NAME: string; iconProp: string; }' is not assignable to type 'number | IProps'.
   Object literal may only specify known properties, and 'INVALID_PROP_NAME' does not exist in type 'IProps'.
-tests/cases/compiler/nonObjectUnionNestedExcessPropertyCheck.ts(16,7): error TS2322: Type '{ nestedProp: { asdfasdf: string; }; iconProp: string; }' is not assignable to type 'number | IProps'.
-  Type '{ nestedProp: { asdfasdf: string; }; iconProp: string; }' is not assignable to type 'IProps'.
-    Types of property 'nestedProp' are incompatible.
-      Type '{ asdfasdf: string; }' has no properties in common with type '{ testBool?: boolean; }'.
-tests/cases/compiler/nonObjectUnionNestedExcessPropertyCheck.ts(19,56): error TS2326: Types of property 'nestedProps' are incompatible.
-  Type '{ INVALID_PROP_NAME: string; iconProp: string; }' is not assignable to type 'IProps'.
-    Object literal may only specify known properties, and 'INVALID_PROP_NAME' does not exist in type 'IProps'.
+tests/cases/compiler/nonObjectUnionNestedExcessPropertyCheck.ts(16,49): error TS2322: Type '{ nestedProp: { asdfasdf: string; }; iconProp: string; }' is not assignable to type 'number | IProps'.
+  Types of property 'nestedProp' are incompatible.
+    Type '{ asdfasdf: string; }' is not assignable to type '{ testBool?: boolean; }'.
+      Object literal may only specify known properties, and 'asdfasdf' does not exist in type '{ testBool?: boolean; }'.
+tests/cases/compiler/nonObjectUnionNestedExcessPropertyCheck.ts(19,56): error TS2322: Type '{ nestedProps: { INVALID_PROP_NAME: string; iconProp: string; }; }' is not assignable to type 'number | INestedProps'.
+  Types of property 'nestedProps' are incompatible.
+    Type '{ INVALID_PROP_NAME: string; iconProp: string; }' is not assignable to type 'IProps'.
+      Object literal may only specify known properties, and 'INVALID_PROP_NAME' does not exist in type 'IProps'.
 
 
 ==== tests/cases/compiler/nonObjectUnionNestedExcessPropertyCheck.ts (3 errors) ====
@@ -29,16 +30,17 @@ tests/cases/compiler/nonObjectUnionNestedExcessPropertyCheck.ts(19,56): error TS
     
     // Nested typing works here and we also get an expected error:
     const propB2: IProps | number = { nestedProp: { asdfasdf: 'test' }, iconProp: 'test' };
-          ~~~~~~
+                                                    ~~~~~~~~~~~~~~~~
 !!! error TS2322: Type '{ nestedProp: { asdfasdf: string; }; iconProp: string; }' is not assignable to type 'number | IProps'.
-!!! error TS2322:   Type '{ nestedProp: { asdfasdf: string; }; iconProp: string; }' is not assignable to type 'IProps'.
-!!! error TS2322:     Types of property 'nestedProp' are incompatible.
-!!! error TS2322:       Type '{ asdfasdf: string; }' has no properties in common with type '{ testBool?: boolean; }'.
+!!! error TS2322:   Types of property 'nestedProp' are incompatible.
+!!! error TS2322:     Type '{ asdfasdf: string; }' is not assignable to type '{ testBool?: boolean; }'.
+!!! error TS2322:       Object literal may only specify known properties, and 'asdfasdf' does not exist in type '{ testBool?: boolean; }'.
     
     // Want an error generated here but there isn't one.
     const propA1: INestedProps | number = { nestedProps: { INVALID_PROP_NAME: 'share', iconProp: 'test' } };
                                                            ~~~~~~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2326: Types of property 'nestedProps' are incompatible.
-!!! error TS2326:   Type '{ INVALID_PROP_NAME: string; iconProp: string; }' is not assignable to type 'IProps'.
-!!! error TS2326:     Object literal may only specify known properties, and 'INVALID_PROP_NAME' does not exist in type 'IProps'.
+!!! error TS2322: Type '{ nestedProps: { INVALID_PROP_NAME: string; iconProp: string; }; }' is not assignable to type 'number | INestedProps'.
+!!! error TS2322:   Types of property 'nestedProps' are incompatible.
+!!! error TS2322:     Type '{ INVALID_PROP_NAME: string; iconProp: string; }' is not assignable to type 'IProps'.
+!!! error TS2322:       Object literal may only specify known properties, and 'INVALID_PROP_NAME' does not exist in type 'IProps'.
     
\ No newline at end of file
diff --git a/tests/baselines/reference/objectLiteralsAgainstUnionsOfArrays01.errors.txt b/tests/baselines/reference/objectLiteralsAgainstUnionsOfArrays01.errors.txt
index 5260d6a8da6d3..2959f29bbc984 100644
--- a/tests/baselines/reference/objectLiteralsAgainstUnionsOfArrays01.errors.txt
+++ b/tests/baselines/reference/objectLiteralsAgainstUnionsOfArrays01.errors.txt
@@ -1,7 +1,6 @@
 tests/cases/compiler/objectLiteralsAgainstUnionsOfArrays01.ts(10,5): error TS2322: Type '{ prop: number; }' is not assignable to type 'Bar | Bar[]'.
-  Type '{ prop: number; }' is not assignable to type 'Bar'.
-    Types of property 'prop' are incompatible.
-      Type 'number' is not assignable to type 'string'.
+  Types of property 'prop' are incompatible.
+    Type 'number' is not assignable to type 'string'.
 
 
 ==== tests/cases/compiler/objectLiteralsAgainstUnionsOfArrays01.ts (1 errors) ====
@@ -17,9 +16,8 @@ tests/cases/compiler/objectLiteralsAgainstUnionsOfArrays01.ts(10,5): error TS232
       { bar: { prop: 100 } }
         ~~~
 !!! error TS2322: Type '{ prop: number; }' is not assignable to type 'Bar | Bar[]'.
-!!! error TS2322:   Type '{ prop: number; }' is not assignable to type 'Bar'.
-!!! error TS2322:     Types of property 'prop' are incompatible.
-!!! error TS2322:       Type 'number' is not assignable to type 'string'.
+!!! error TS2322:   Types of property 'prop' are incompatible.
+!!! error TS2322:     Type 'number' is not assignable to type 'string'.
 !!! related TS6500 tests/cases/compiler/objectLiteralsAgainstUnionsOfArrays01.ts:2:3: The expected type comes from property 'bar' which is declared here on type 'Foo'
     ]
     
\ No newline at end of file
diff --git a/tests/cases/compiler/excessPropertyCheckWithUnions.ts b/tests/cases/compiler/excessPropertyCheckWithUnions.ts
index bb3e59151fc2a..635c5c2a7d3f6 100644
--- a/tests/cases/compiler/excessPropertyCheckWithUnions.ts
+++ b/tests/cases/compiler/excessPropertyCheckWithUnions.ts
@@ -87,3 +87,29 @@ const obj: Union = {
     // should have error here
     href: 'foo',
 };
+
+// Repro from #34611
+
+interface IValue {
+  value: string
+}
+
+interface StringKeys { 
+    [propertyName: string]: IValue;
+};
+
+interface NumberKeys {
+    [propertyName: number]: IValue;
+}
+
+type ObjectDataSpecification = StringKeys | NumberKeys;
+
+
+const dataSpecification: ObjectDataSpecification = {  // Error
+    foo: "asdfsadffsd"
+};
+
+// Repro from #34611
+
+const obj1: { [x: string]: number } | { [x: number]: number } = { a: 'abc' };  // Error
+const obj2: { [x: string]: number } | { a: number } = { a: 5, c: 'abc' };  // Error