keywords: Internet Explorer IE devenv devenv.exe crash mvc 5 freezes
There are a few fixes out there that didn’t work for me.

I deleted the IISEXPRESS Folder and added _CSRUN_DISABLE_WORKAROUNDS to system environmental variables rebooted etc. No luck (though this has worked for others).

What I had to do to fix: Open Visual Studio in /safemode as administrator. Then add the ASP.NET Web Project to the solution in Visual studio.

Worked first time.  Could be an add-on.