Reinitialising (resetting) Offline Files

Reinitialising (reset) the cache and database of Offline Files (http://support.microsoft.com/kb/230738)

Method 1.

The Offline Files cache is a folder structure located in %SystemRoot%\CSC, which is hidden by default. Do not modify the CSC folder or any files and subfolders it contains directly; doing so can cause data loss and complete failure of Offline Files.
If you suspect database corruption, remove the files through the Offline Files viewer. After removing them, you can force file synchronisation using Synchronization Manager. If the cache still does not work correctly, clear the Offline Files cache using the following procedure:

1. On the Offline Files tab in the Folder Options dialog box, hold down CTRL+SHIFT and click Delete Files. The following message appears:
   The Offline Files folder on this computer will be reinitialised. Any changes made offline that have not been synchronised will be lost. Files and folders marked for offline use will no longer be available offline. A computer restart is also required.

   Do you want to reinitialise the Offline Files folder?

2. Click Yes twice to restart the computer.

Method 2.

If the Offline Filestab is unavailable, use this method to reinitialise the Offline Files cache (CSC) by editing the registry. This method can also reinitialise the client's Offline Files database and cache on multiple systems. Add the following registry subkey:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\NetCache
Key name: FormatDatabase
Key type: DWORD
Key value: 1

Note: The actual registry value is ignored. This registry change requires a restart. During restart, the system reinitialises the CSC cache and removes this registry entry if it exists.

Warning: All cached files will be deleted and all unsynchronised data will be lost.