Exchange 2013 server 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.
The applicationHost.config file was messed up. For me the file was completely empty. Not a line of code to be found.
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.
WAS starts successfully then you should be able to start the WWW Publishing Service.