I have a windows 7 Professional PC that is losing the connection to the domain DFS shares every couple days. When the user tries to access his mapped drives he gets a message "<drive letter> is not accessible. The system cannot open the file." We have 2 DFS servers; 1 onsite is Windows 2003 R2 SP2, 1 off site is Windows 2008 R2 SP1. When the problem occurs, unable to access the DFS by \\<domain name>\dfs or by \\<2003 server name>\<share name>. Can however get to the directories if we try \\<2008 server name>\<share name>. No error logs appear in the event viewer. Log off and back on doesn't fix nor does rebooting. The only "fix" we have found so far is to run gpupdate /force to get all the mappings active again. We have checked the DNS servers to be sure they are up to date and double checked the DNS on the PC. We have removed all of the power settings that would turn off the NIC as well as changed settings to keep the PC from hibernating. Scanned for any Malware or viruses. Switched the primary and secondary DNS servers so that the PC uses the DNS server on the off site segment to see if that would help. We tried to install a hotfix that seemed to fit what I was experiencing but was told that it didn't apply to the operating system. Found the solution to add the LMCompatibilityLevel registry entry and tried that with no success as well. User is a local admin and able to get out to internet and email when the DFS disconnects. Thanks in advance, Tim A.

Hi Tim, Only this computer got the issue? How about others? How about removing this client then rejoining the domain? Since you mentioned when force update the group policy, all mapping drives work again. I suspect the GPO are not applied correctly on this Windodws 7 client. Check the system logs on your Windows 7 system log, are there any related with the GPO? If no clue found, I suggest you collect GPSVC Logging to make sure GPO is applied on your client. Refer to: Userenvlog for Windows Vista/2008/Win7 Regards, MiyaThis posting is provided "AS IS" with no warranties, and confers no rights. | Please remember to click "Mark as Answer" on the post that helps you, and to click "Unmark as Answer" if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Thanks for the reply Miya. I will be visiting this client to day and will try the remove and rejoining of the client to the domain. I don't believe there were any errors but I will double check to be sure. Thanks again, Tim A.

Miya, Tried removing and then re-adding to the domain and it worked for a couple days then cut the user off again. Checked the system log as well as the GP log and there are no errors. This last time he experienced the problem he had been working fine for 4 hours then suddenly it dropped the connection to his network drives. As of this time, this is the only PC with a problem that has been reported. Hard to say since this client is primarily an XP location. Tim Adams

Hi Tim, How about change another user account? Any related events on your server? When did this issue happen? Since this client was clean installed? Is it OEM version or self-deployed? This situation is strange and really hard to troubleshoot. Please also update the network card driver and BIOS to the latest one. Regards, MiyaThis posting is provided "AS IS" with no warranties, and confers no rights. | Please remember to click "Mark as Answer" on the post that helps you, and to click "Unmark as Answer" if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Miya, Little difficult to change to a different account since we are not always nearby when this happens. I know that him logging off then back on doesn't fix it but I can see that switching user accounts would help discern whether it is a corrupt profile or a problem with his account. Have not seen any problems on the server around the same time as the problems. This PC has only been on-site about a month and the problem started shortly after that. It was a clean install. Should have been an OEM license that was installed. I will look into updating the NIC and BIOS as well. Tim A.

Visited client and did as requested. NIC driver was up to date but updated the NIC software to latest version. Updated BIOS as well. We also ran sfc /scannow and found a couple of files that were fixed. We are now waiting to see if the problem happens again. Tim A.

Hi Tim, If issue persists, I suggest you check the group policy on the clients both when it's working and not working. Open an elevated prompt, input the command: gpresult /h gpreport.html Then you'll get a report. Comparing them to find if there's any difference after the issue happen. Regards, MiyaThis posting is provided "AS IS" with no warranties, and confers no rights. | Please remember to click "Mark as Answer" on the post that helps you, and to click "Unmark as Answer" if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Looks like run SFC /SCANNOW fixed the problem. The problem has not resurfaced now in over a week. Thanks for the advice Miya

Glad to hear the issue is resolved:) Cheers, MiyaThis posting is provided "AS IS" with no warranties, and confers no rights. | Please remember to click "Mark as Answer" on the post that helps you, and to click "Unmark as Answer" if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

This had me spongebob'd for a while then I changed my fixed IP address to a reservation in DHCP and the problem was resolved. Hope this helps someone. Cheers, D

I know this is an old post, but I had the same issue and found this: http://support.microsoft.com/kb/983620 In short is decribes the issue I was having and it fixed the issue for me (the work around also worked too).