Unable to start debugging on the web server

“Unable to start debugging on the web server” is a common issue for ASP.NET developers but there can be various reasons for the occurrence this issue. I myself spent some time to resolve the issue on my machine.That’s why I decided to write an article on this topic to list down the possible solutions to this problem. Off course there may be other solutions depending upon the scenario that leads to the same problem.
So, following is my guideline in solving this problem :
1. First of all we need to check the debug configuration, debug mode is enabled? If its not, please enable it by following the link.2. If there are any syntax error in web.config, please remove those to enable debugging.

3. We need to verify that the Application Pool we are using is started or not. There might be some errors that shutdown the App Pool. How to start Application Pool, follow the link.

4. Further, we needs to verify that App Pool is running under valid account. It may vary for different environments i.e. for my machine, its running under ApplicationPoolIdentity built-in account.

5. Verify and App Pool to appropriate framework version.

6. I have seen that for some scenarios where we are using URLRewrite module, same problem can occur. So, we need to remove or comment the those entries from web.config to make it working.

Hopefully, following these steps will resolve the issue. Please add comments if you have a different solution to this problem. Thanks.