ASPNET_WP.EXE couldn't start anymore

[lalberti]

Somehow my ASPNET_WP.EXE couldn't start anymore. The two error messages
related to this from the event viewer were:
Event Source: ASP.NET 1.1.4322.0
aspnet_wp.exe could not be started. HRESULT for the failure: 80004005
Event Source: ASP.NET 1.1.4322.0
aspnet_wp.exe could not be launched because the username and/or password
supplied in the processModel section of the config file are invalid.

I suspect the reason might be my incidental change of the ASPNET account
password in my WindowsXP. Afterwared, I went to the Machine.Config file
and changed the <ProcessModel's user to system (the original one was
machine) and password. It still didn't work. Could anyone tell me what would
be the likely reason and how to fix it other than reinstalling my .NET
framework?

Many thanks,

Luca