In 2012 Revit products, things got moved and switched around when dealing with the Revit.ini file.
In 2013, an additional tweak has been made, the UserDataCache directory has been moved from the Program Files directory over to ProgramData. This makes things a little bit less dicey (as Microsoft doesn't really want user modified/customized stuff to live in Program Files). If your doing any Revit.ini updating, its good to know that the new UserDataCache directory is over in C:\ProgramData\Autodesk\RVT 2013\UserDataCache.
For some additional goodies on UserDataCache and the Revit.ini check out the 2013 wikihelp:
- What is the relationship between the Revit.ini files?
- What happens to the UserDataCache and user profile file structure when Revit
runs for the first time?
- The Revit.ini File