FatalExecutionEngineError after Windows 10 Anniversary Update

[dmarklein]

After installing the Windows 10 Anniversary Update (and re-installing IIS, since the update removed it), we are unable to run our local development websites in IIS 10.

Now, whenever we attempt to access on our local dev websites through a browser, we see the following:

In the event log, we see corresponding errors like the following:

Log Name: Application
Source: Application Error
Date: 9/22/16 10:57:46 AM
Event ID: 1000
Task Category: (100)
Level: Error
Keywords: Classic
User: N/A
Computer: DANIELKLEIN232E
Description:
Faulting application name: w3wp.exe, version: 10.0.14393.0, time stamp: 0x57899b8a
Faulting module name: clr.dll, version: 4.6.1586.0, time stamp: 0x575a1507
Exception code: 0xc0000005
Fault offset: 0x0000000000099a99
Faulting process id: 0x1270
Faulting application start time: 0x01d214ea0ede0a43
Faulting application path: c:\windows\system32\inetsrv\w3wp.exe
Faulting module path: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\clr.dll
Report Id: 2b14898a-5bcc-4fb6-a8aa-8fa9fe16f6d2
Faulting package full name:
Faulting package-relative application ID:
Event Xml:

Furthermore, I have debugged one of the web sites -- watching in the debugger, we make it through the Application_Start just fine, but then immediately thereafter the exception is thrown. We originally thought this was related to #1583, so we tried installing/repairing .NET Core as well as repairing VS2015, to no avail.

We are at a complete loss -- any help and/or a workaround would be greatly appreciated. Until then, we are all going to roll back to prior to the Anniversary update.

[pranavkm]

watching in the debugger, we make it through the Application_Start just fine

Is this a WebForms\ Mvc 5 application?

[dmarklein]

Yes -- our sites use WebForms and MVC5 in conjunction.

[pranavkm]

@DamianEdwards where should we track this issue?

[DamianEdwards]

Adding @csharpfritz

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