I'm running a simple ArcMap add-in in Visual Studio and am getting this error:
Severity Code Description Project File Line Suppression State Error The "ValidateAddInXMLTask" task failed unexpectedly. System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.VisualStudio.Shell.12.0, Version=126.96.36.199, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified. File name: 'Microsoft.VisualStudio.Shell.12.0, Version=188.8.131.52, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' at ESRI.ArcGIS.AddIns.SDK.MSBuild.ValidateAddInXMLTask.Execute() at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute() at Microsoft.Build.BackEnd.TaskBuilder.d__26.MoveNext()
WRN: Assembly binding logging is turned OFF. To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1. Note: There is some performance penalty associated with assembly bind failure logging. To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog]. FirstAddIn
I'm using ArcGIS for Desktop and ArcObjects SDK for .NET version 10.4. I obtained my Arc license and SDK via ISO on MyEsri and for this add-in I'm using .NET 4.5.
My issue seems very similar to this one as I also got the same dialog box pictured there, but in the accepted answer it has me check Use Managed Compatibility Mode and it was grayed out when I tried it. I also had no luck with the other answers. I'm new to Visual Studio.