Application Crashes With "Internal Error In The .NET Runtime"

Question

with exit code 80131506

That's a nasty one, ExecutionEngineException. Starting with .NET 4.0, this exception immediately terminates the program. The generic cause is corruption of the state of the garbage collected heap. Which in turn is invariably caused by unmanaged code. The exact location in code at which this exception is raised isn't helpful, the corruption usually occurred well before the damage is detected.

Finding the exact cause for this is going to be difficult. Review any unmanaged code your service might be using. Suspect environmental problems if there is no obvious candidate, misbehaving malware scanners are notorious. If it repeats very poorly then suspect hardware problems like soft RAM errors.

A bug in the concurrent implementation of the Garbage Collection on x64 .Net 4 can cause this as stated in the following microsoft KB entry:

ExecutionEngineException occurs during Garbage Collection

You should first make a deep minidump exploration to be sure that the problem occured during a Garbage collection.

The minidump location can usually be found in a Windows Error Reporting entry in the event log following the crash entry. Then, have fun with WinDbg !

The latest documentation on the use of the <gcConcurrent/> configuration element, to disable concurrent or (in .NET 4 and later) background garbage collection, can be found here.

I've experienced "internal errors" in the .NET runtime that turned out to be caused by bugs in my code; don't think that just because it was an "internal error" in the .NET runtime that there isn't a bug in your code as the root cause. Always always always blame your own code before you blame someone else's.

Hopefully you have logging and exception/stack trace information to point you where to start looking, or that you can repeat the state of the system before the crash.

For those arriving here from google, I've eventually come across this SO question, and this specific answer solved my problem. I've contacted Microsoft for the hotfix through the live chat on support.microsoft.com and they sent me a link to the hotfix by email.

Had the same exact error on WinXP box with latest build of my .NET 4 code. Checked previous builds - now they crash too! Ok, so it's not me :). No suggestions here/above helped.

Much more recent (2018-05-09) report of the same problem: Application Crash with exit code 80131506.

A: We were receiving a similar error, but we believe ours was caused by the Citrix memory optimizer.
The resolution was to force a regeneration of the .Net core libraries on the host(s) where the issue was occurring:
C:\Windows\Microsoft.NET\Framework64\v4.0.30319\ngen.exe update /force

Root cause is still unknown (machine is not being updated and has little use), but that did it for me!