title: 0xc00000fd Error and Debug Diag freeze IIS
body: <p>we have 2 servers where are getting a recurring 0xc00000fd error, also on occasion, we get an app pool time out the restarts the app pool without the error that I think this is related.
  when the error occurs it creates a Just in Time debugger that does not really tell us anything and if you clear the error the app pool restarts.</p>
  <p>everything I have read says that the only way to get to the bottom of this is to use the MS Debug 2 Collection tool, the problem is when I set this up the we site connected to the app pool freezes</p>
  <p>in the log file we get</p>
  <p>Loading control script C:\Program Files\DebugDiag\scripts\CrashRule_WebAppPool_AppPoolName.vbs
  DumpPath set to C:\Temp\NG Dump
  [09/11/2021 22:20:51]
  DebugDiag version 2.3.2.11
  DbgHost version 2.3.2.11
  DbgSvc version 2.3.2.11
  Process created. BaseModule - c:\windows\system32\inetsrv\w3wp.exe. BaseThread - System ID: 51980
  C:\Windows\SYSTEM32\ntdll.dll loaded at 0x20250000
  Thread created. New thread - System ID: 42032
  Thread created. New thread - System ID: 18512
  Thread created. New thread - System ID: 17228
  Thread created. New thread - System ID: 38064
  Thread created. New thread - System ID: 19380
  Thread created. New thread - System ID: 43580
  Thread created. New thread - System ID: 38236</p>
  <p>this Thread Created occurs till I kill the tool in task manager then the App pool restarts</p>
  <p>the full error is</p>
  <p>Faulting application name: w3wp.exe, version: 10.0.14393.0, time stamp: 0x57899b8a
  Faulting module name: KERNEL32.DLL, version: 10.0.14393.4651, time stamp: 0x613d606a
  Exception code: 0xc00000fd
  Fault offset: 0x0000000000011cb9
  Faulting process id: 0x99ec
  Faulting application start time: 0x01d7d5b5ce17180f
  Faulting application path: c:\windows\system32\inetsrv\w3wp.exe
  Faulting module path: C:\Windows\System32\KERNEL32.DLL
  Report Id: 33883336-dfca-425a-82d7-3e2e35371ff8
  Faulting package full name:
  Faulting package-relative application ID:</p>
  <p>or</p>
  <p>Faulting application name: w3wp.exe, version: 10.0.14393.0, time stamp: 0x57899b8a
  Faulting module name: clr.dll, version: 4.7.3850.0, time stamp: 0x60d67f8a
  Exception code: 0xc00000fd
  Fault offset: 0x00000000000de810
  Faulting process id: 0x4694
  Faulting application start time: 0x01d7d51a2bde2f57
  Faulting application path: c:\windows\system32\inetsrv\w3wp.exe
  Faulting module path: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\clr.dll
  Report Id: 9d7ac2a9-7cba-49c1-a35f-f3748f108183
  Faulting package full name:
  Faulting package-relative application ID:</p>
  <p>we have Windows Server 2016 , the web app is based on .net 4.5.2 IIS runs on one system and the SQL server is a separate server.
  We have tried setting the debug tool up to monitor the whole of IIS and a specific app pool just for this error but the result is the same the site stops until the debug collection service is killed off.</p>
  <p>Does anyone have any ideas's what the issue might be or how to figure it out?</p>