The error seems to indicate a problem with .NET, which is quite strange, since the Couatl64 .exe is NOT a .NET app, it's a native x64 app that doesn't do any call to the .NET framework. So, I wonder if this might be something else entirely, like another app (antivirus, maybe) that DOES use .NET and attaches to the Couatl64.exe, which is what antivirus usually do to check.