Faulting application name: w3wp.exe, version: 7.5.7601.17514, time stamp: 0x4ce7a5f8
Faulting module name: clr.dll, version: 4.0.30319.18063, time stamp: 0x526767c6
Exception code: 0xc00000fd
Fault offset: 0x0007717d
Faulting process id: 0x1728
Faulting application start time: 0x01cf972772f04132
Faulting application path: C:\Windows\SysWOW64\inetsrv\w3wp.exe
Faulting module path: C:\Windows\Microsoft.NET\Framework\v4.0.30319\clr.dll
Report Id: b4d0c430-031a-11e4-a40f-0050569e40da

Keep getting this error when our MSM module loader service crashes? We loaded the hotfix supplied with the windows updates and no improvement.

Any ideas as to why?

tldr:

I have faced the same error. It was due to a client repeatedly calling a WCF service, where a method called itself recursively, thus throwing StackOverflowException.

Long answer:

This was happening in a WCF application using .Net 4.5. All our services (.svcs), started failing one by one, until the whole application pool started to give error HTTP 503. The app pool was dead.

Digging through the application logs, then EventViewer logs, we found the same message as the OP.

For a while we kept restarting the app pool, but it would only crash again after some time.

The app pool suddenly stabilized itself at 2pm, and we have some system operation that run noon to 2pm... We figured it must have something to do with that. We were able to found it was due to a merge error where a Method keeping calling itself recursively, the method had no parameters or return type. Probably it threw so StackOverflowExceptions causing the application pool to crash.