February 11, 2008: Troubleshooting XP's Offline files
I recently had an a problem with XP’s Offline Files. The system was XP Pro SP2 with all updates thru Feb 2008. Folder Redirection of the users’s Desktop and My Documents folders is accomplished via Group Policy from the domain; the user had then set Offline Files to keep a local cache of the redirected folders. The computer displayed the following symptoms:
- Offline files never synchronize
- mobsync.exe (the Synchronization Manager) ate lots of CPU for days on end, and on shutdown or logoff, failed to gracefully shutdown, presenting dialog with “The program is not responding”
- The mapped drive where the offline files were redirected to (by domain policy) didn’t show all files that should be there - even the files/folders outside the redirected folders were incomplete.
- dir \domainname\sysvol failed - this was a big problem! GPO’s could not be applied
- Because of above, gpupdate /force would always create a USERENV 1058 error in Application Log
- logout took a really long time
It wasn’t really a pressing problem, but it was on my to-do list. I took a stab at it from time to time but never quite solved it. Today I finally took a systematic approach to the problem. Notice that it looks like two separate issues - GPOs failing to apply, and the local DFS client being terribly confused.
What finally did it was the following, in concert:
- dfsutil /purgemupcache (dfsutil.exe is in the Windows 2003 Support Tools)
- Checked the following Registry values (two were not present): HKLM\System\CurrentControlSet\Services\Mup\DisableDFS=0
HKLM\Software\Policies\Microsoft\Windows\NetCache\Enabled=1
HKLM\Software\Microsoft\Windows\CurrentVersion\NetCache\Enabled=1
(The first is documented at EventID; the other two are documented by Jonathan Hardwick.) - Kill the mobsync.exe process
- Re-initialize CSC cache as explained in Method 1 at KB230738. (Note that performing this step without killing mobsync didn’t have any effect.)
- Reboot the system as directed.
After the reboot, both the GPO problem and the DFS problem went away, and I was easily able to Synchronize Offline Files. Finally, this nagging issue was off my plate. Hallelujah!
The interesting thing about this is that the Event Log was full of pointers to the GPO problem, but had nothing about the DFS problem, which was the real root of the issue. It’s just another reminder that the Troubleshooting Ninja needs to avoid tunnel vision and stay aware of all the symptoms a sick computer displays. And (regrettably), XP’s DFS client needs to log more to the Application Log!