Exchange Server 2013 MSRC Security bulletin MS13-061

** Exchange 2013 Security Update has been pulled **
Update 14/08/13: Due to an issue with the Exchange 2013 Security Update installation process, the Exchange 2013 updates have been removed from the Download Center. For more information, please see Exchange 2013 Security Update MS13-061 Status Update.

Please see the following;
Security fix MS13-061 breaks content index on Exchange Server 2013

Content index (CI) for mailbox databases shows Failed on affected server.

The Microsoft Exchange Search Host Controller service is missing.

You see a new service named "Host Controller service for Exchange".

To work around the problem, update the following registry entries.

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Search Foundation for Exchange

Set the value of the DataDirectory registry entry to the Data directory path for your Exchange Server installation.

For example if your Exchange installation directory is C:\Program Files\Microsoft\Exchange Server\V15.
Then set the value of the DataDirectory registry entry to:

"C:\Program Files\Microsoft\Exchange Server\V15\Bin\Search\Ceres\HostController\Data".

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\HostControllerService

- Set the value of the DisplayName registry entry to "Microsoft Exchange Search Host Controller".
- Add a new Multi-String Value named DependOnService and set its value to "http".
- Restart the Microsoft Exchange Search Host Controller service.

Note Change to the service display name will take effect after you restart the server.

There is also a script located here that will provide the necessary workaround.