How UPM Active write back Registry works

Instructions

1. User login, download NTUSER.DAT from user store
2. User makes changes to the HKCU registry, the changes will be cached locally and then synced to the user store on a 5 minutes basis (only update the changes during the 5 minutes). During the sync process, the NTUSER.DAT will be locked, and the following sync requests will await.
3. User logoff, write back the changes since the last active write back process.