If you have Windows Server 2008 R2 & having problem to start Internet Information Services IIS due to Windows Process Activation Service (WAS) unable to Start or file missing (“file not found”) you want to do the following.
- Uninstall Windows .net Framework 3.5
- Uninstall Windows Process Activation Service (WAS)
- Uninstall IIS
- Restart the server
- Re-install IIS
It works for me.