If you’re using vs.net and want to debug your code, using the Debug > Attach to process… option you may notice that there can be more than one w3wp.exe processes running with different ID’s. So which one should you choose?
Here is and easy way to figure out wow to select.
You open en command prompt, type “IISAPP” and press Enter (no additional parameters)
NOTE! On Windows Server 2008 IISAPP doesn’t exist so use this command instead – the results are the same.
%windir%\system32\inetsrv\appcmd.exe list wp
You should now have a list of running web applications in your (IIS) Internet Information Services like this