The file version of System.Web.Http.dll in https://www.nuget.org/packages/Microsoft.AspNet.WebApi.Core/ nuget has actually decrement with the 5.2.8 nuget release. The **5.2.8** version of Microsoft.AspNet.WebApi.Core nuget package has System.Web.Http.dll File Version: **5.2.34876.0** Product Version: 5.2.8-34876 (005f94e123afdf3111f23f0b982880f8db9b10a7) The **5.2.7** version of Microsoft.AspNet.WebApi.Core nuget package has System.Web.Http.dll File Version: **5.2.61128.0** Product Version: 5.2.7-61128 (39d3064baf13181f5718ec5d85ba644b47d0704b) This causes installer issue when performing upgrades as the version decremented instead of incrementing.