Well this is going to be detailed answer but I would like to share my experience in resolving the HTTP Error 500.19, specifically the internal server error code 0x8007000d. After considerable frustration and numerous attempts to implement various solutions found on platforms like Stack Overflow, YouTube and Microsoft Documentation, I was able to identify and fix the issue. Below is a detailed account of the steps I took in last 2 days:

Initial Troubleshooting Steps

1. Installed .NET 6 Hosting Bundle: Ensured that the necessary hosting components for .NET 6 were installed.
2. Installed .NET 6 SDK and Runtime: Verified that both the SDK and runtime were correctly installed to support the application.
3. Installed URL Rewrite Module: Added the URL Rewrite Module to manage URL routing effectively.
4. Installed ARR Module: Set up the Application Request Routing (ARR) module for load balancing and reverse proxy capabilities.
5. Revised Web.config: Reviewed and modified the web.config file for the application to ensure proper configuration.
6. Reinstalled IIS: As a last resort, I reinstalled Internet Information Services (IIS) to reset the environment.
7. Reconfigured Default Web Site: Recreated the Default Web Site in IIS along with all associated application pools.
8. Deleted and Recreated wwwroot: Cleared the C:\inetpub\wwwroot directory and set it up anew.
9. Published Application Locally: Built the application locally and deployed it to IIS as a new application.
10. Checked All Modules at Various Levels: Reviewed all installed modules across IIS, the Default Web Site, and the applications under the Default Web Site to ensure proper configuration and functionality.

Successful Resolution Steps

After extensive troubleshooting, I was able to identify the root cause of the issue through the following steps:

1. Installed .NET 6 Hosting Bundle: Confirmed the installation was successful.
2. Compared Web.config Files: Analyzed the web.config file of my application against a colleague's working version to identify discrepancies.
3. Reviewed ApplicationHost.config: Examined the ApplicationHost.config file, typically located at C:\Windows\System32\inetsrv\config.

Key Findings

• I discovered that the .NET 6 Hosting Bundle was not installed correctly or completely. Specifically, I was missing the AspNetCoreModuleV2, which should be configured to the path: %ProgramFiles%\IIS\Asp.Net Core Module\V2\aspnetcorev2.dll

• Additionally, I found a missing section entry in the system.webServer section group:

  <section name="aspNetCore" overrideModeDefault="Allow" />

• I ensured that my application pool was set to "No Managed Code" for the CLR version, with Integrated Pipeline Mode and using the default application pool identity. I also disabled the option for 32-bit applications in the advanced settings for the application pool. - Finally, I granted the necessary permissions to the IIS_IUSRS user group for my application folder to ensure that IIS could access the web.config file.

Conclusion

After implementing these changes, I was able to successfully run the application on my system. I hope this detailed account of my troubleshooting process proves helpful to anyone facing similar issues.