HKEY_LOCAL_MACHINE\software\policies\microsoft\office\15.0\common\fileio

Open Directly in Office Client Application
- HKEY_LOCAL_MACHINE\software\policies\microsoft\office\15.0\common\fileio\opendirectlyinapp
Set the max size of the Office Document Cache
- HKEY_LOCAL_MACHINE\software\policies\microsoft\office\15.0\common\fileio\maxcachesize
Age out documents older than n days
- HKEY_LOCAL_MACHINE\software\policies\microsoft\office\15.0\common\fileio\ageoutpolicy