Resetting corrupt "always available offline" database

For my work computer I keep a Outlook Data File (.pst), as a place to backup email. I keep the pst-file on my network share, which ensure that it’s backed up. Recently I’ve experienced trouble with this solution when I’ve disconnected from the network while Outlook is running. I end up with a corrupt Offline Files Database which fail when syncing the pst-file. I can access the file while I’m not connected to a network, but as soon as I connect the file size appear to be 0 kB.

The only solution I’ve found to this problem is to reset the Offline Files Database, via Delete Offline Files Cache Windows 7 and this from Microsoft.

You can do this by setting a flag in the registry.

  1. Open regedit
  2. Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\CSC\Parameters
  3. Create a new REG_DWORD named FormatDatabase with a value of 1
  4. Restart computer
  5. Add folders to the Offline Files Database

It’s important to remember to re-add the folders to make them available offline again after the restart.

To reapply group policies use the command (from this page):

gpupdate /force