IIS Application pool stop every 15 days without any configuration

On a Windows instance a specific application pool stops every 15 days and we have to manually restart that Under the event logs we are getting dotnet clr.dll error given below.

Faulting application name: w3wp.exe, version: 10.0.17763.1, time stamp: 0xcfdb13d8 Faulting module name: clr.dll, version: 4.7.3610.0, time stamp: 0x5e13fa89 Exception code: 0xc00000fd Fault offset: 0x000000000012ebdc Faulting process id: 0x2678 Faulting application start time: 0x01d7069cd23d6f15 Faulting application path: c:\windows\system32\inetsrv\w3wp.exe Faulting module path: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\clr.dll Report Id: b44401f0-97b2-4b8c-8fba-703227faec12 Faulting package full name: Faulting package-relative application ID:

What should be the process for debugging this issue to get the root cause?

I am new to server management and processes so please bear with me.

Thanks in advance.

It looks like you have a StackOverflow Exception, which is caused by unbounded recursion (a function repeatedly calling itself, etc). You can track the problem down using DebugDiag and WinDbg.

DebugDiag can be configured to generate a crash dump when the StackOverflowException occurs.

Download at Debug Diagnostic Tool.

About how to use the Debug Diagnostics tool to troubleshoot a process that has stopped responding in IIS you can refer to this link: How to use the Debug Diagnostics tool.

Debugging tools for Windows is part of the Windows SDK and can be downloaded at Download the Windows Driver Kit (WDK). To use WinDbg, you'll need to get the symbols files. Download the symbol files and put them in a local folder. Getting Started with WinDbg.

In the results, it should be clear what the problem is.