Recently had the Ultimate Visual Studio nightmare. No matter what the Project, VSTO would crash.
This should apply to all versions since, say 2008 but in my case it was 2010 Ultimate.
The bug was a duplicate install of Telerik NuGet packages so the real fix is to remove all Telerik Nuget packages I suppose.
But I was recently reminded of a troubleshooting trick in VSTO from the old command line.
Run : devenv.exe /log “C:\ActivityLog.xml” And Voila all of your errors are cleanly reported.
So whatever the problem you should know what to do next.
Happy Coding !!!