HTTP Error 502.5 - Process Failure after Deployed the .Net core to Azure appservice - azure

Question

I have recently upgraded my .Netcore webapi from 2.2 to 3.1 and deployed to azure app services.
Since then I got the below issue. I have reverted the release but still getting the same error.
I found few solutions for IIS but nothing for Azure app services .How to fix this?

Answer 1

[NEWEST]
Solution:
Reduce the version of Microsoft.Extensions.Configuration.Abstractions to 3.1.17 or 3.1.16.
Troubleshooting:
Try to find Microsoft.Extensions.Configuration.Abstractions on scm site.
I guess it don't include Microsoft.Extensions.Configuration.Abstractions package when deploy, so try to use below code in .csproj file. But it failed.
I try to find the reason on scm site, and I find it. On azure, .net core 3.1 just support the version of Microsoft.Extensions.Configuration.Abstractions are 3.1.17 and 3.1.16.
[PREVIOUS] The way to find the error logs
Judging from the error message, your webapp did not start. To solve the problem, we can only locate the error by querying the log.
You have the following two solutions to solve the problem. View the log:
Prerequisite: If you have successfully deployed the project before, please log in to the scm site to clean up all the files in the original wwwroot folder.
Plan 1:
Find the web.config file in the wwwroot folder and set stdoutLogEnabled="true".
You can refer to the following posts and github issues.
Azure Web App - Python: can't open file 'manage.py': [Errno 0] No error
How to enable stdoutLogEnabled=true when site is deployed with Run From Package
After add the settings in web.config, we can check the logs.
Plan 2:
Follow below picture, check Application Event Logs.
You also can refer my answer to Collect .NET Profiler Trace (Azure - Unhandled Exception: System.IO.FileNotFoundException).
After find the error, you can solve it quickly. If you also have some problem, you can create a new project without any sensitive info for us to reproduce your issues.