网站无法在Visual Studio中运行，会停止应用程序池

Question

When I try to start my web site in Visual Studio, it gives me an error message and stops the IIS application pool that it was supposed to use. I am using Visual Studio Professional 2013 and ASP.NET MVC with IIS as the server, all running on the same computer under Windows 7 Ultimate. I can reproduce the following steps.

1. Check to ensure that the app pool is running.
2. Press F5 to start debugging. VS gives me an error message that says, "Unable to start debugging on the web server. Could not start ASP.NET debugging. More information may be available by starting the project without debugging."
3. Check the application pool again. It is stopped.
4. Restart the app pool.
5. Press Ctrl-F5 to start the app without debugging.
6. My debugging browser displays a screen that says, "Service Unavailable HTTP Error 503. The service is unavailable."
7. Check the app pool in IIS Manager. It is stopped again.

The project was running fine recently.

I have tried the following:

• Restart Windows.
• Verify that the web app I want to run is the startup project.
• Verify that "Define DEBUG constant" is checked in the Properties page of the project.

• Verify that debugging is set in the Web.Config. file, as follows:

  <compilation debug="true" targetFramework="4.5" />

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Edit:

I checked logs as suggested (Thank you Kenneth!).

The System log has a series of four "Warning" messages with a source of "WAS". They say, "The Windows Process Activation Service failed to create a worker process for the applicatino pool 'SMS Web'. The data field contains the error number.

An error message then appears, also with a source of "WAS" that says, "Application pool 'SMS Web' is being automatically disabled due to a series of failures in the process(es) serving that application pool."

Finally, these messages were followed immediately by a (possibly unrelated) "Information" message with a source of "Service Control Manager" that says, "The Multimedia Class Scheduler service entered the running state."

Answer 1

I had a similar problem with a similar solution:

Scenario: I had the app pool running under an user account and it's password had been changed because it had expired. I never updated IIS so the app pool would stop by itself.

Solution: update the credentials for the account on IIS or use another account

Just posting this in case it helps anyone

Answer 2

If you have configured a username and password in the application pool, then if you have changed the password for that account, you may get this error.

If you changed the password, you'll have to change it there also.