Windows Process Activation Service – Error 13: The data is invalid

I ran into a strange error recently on an Sccm 2012 server. The WWW Publishing Service was stopped. When I tried to start the service it failed on a dependency. A quick check revealed the Windows Process Activation Service (WAS) was stopped. When I tried to start WAS I received the following error.

Windows could not start the Windows Process Activation Service service on Local Computer. Error 13: The data is invalid.

The Event Viewer was littered with equally cryptic Event IDs, such as WAS 5005 and WAS 5036.

Not the first time

I’ve actually encountered an error like this before. I am not sure what causes it. But evidently something in Internet Information Services (IIS) becomes corrupt.

The applicationHost.config file was messed up. For me the file was completely empty. Not a line of code to be found.

Luckily IIS takes backups that can be found in C:\INETPUB\HISTORY. Under here you will see several folders with a prefix of CFGHISTORY. The folder with the highest revision number will be your latest backup. Copy this file and overwrite the existing file at C:\WINDOWS\SYSTEM32\INETSRV\CONFIG.

Once the file has been replaced start the WAS service.

If WAS starts successfully then you should be able to start the WWW Publishing Service. If that starts successfully, then you can restore all Exchange Web Services.