In SP2 (Service Pack 2) for Windows Server 2003, a change was introduced which may affect performance when you map to these drives. Sometimes the slowdown is obvious and others it is not so much.
If you open Windows Explorer and it takes a long time to open, you may have this problem. Try this test:
- Disconnect all mapped drives
- Close Windows Explorer
- Open it again and see if opens quickly
- Map a drive to the DFS share, then map a different drive to the same location using the UNC directly to the server
- Open a file on the DFS mapped drive, close it, then open the same file on the UNC mapped drive.
- If the UNC mapped drive is significantly faster you need this patch
To resolve the problem add the following registry entries to all workstations AND servers:
- Click Start, click Run, type regedit in the Open box, and then click OK.
- Locate and then click either of the following registry subkeys:
- On the Edit menu, point to New, and then click DWORD Value.
- Type NoPreviousVersionsPage, and then press ENTER.
- Right-click NoPreviousVersionsPage, and then click Modify.
- In the Value data box, type 1, and then click OK.
- Quit Registry Editor.