This had been driving me nuts. My situation is I run Windows 7 Pro. Office 2007. Connected to a SBS 2008 Server. When I open an Excel document from the server the first time it would take minutes and sometimes would time out. After this it was fine usually for the rest of the day. Saving a file was the same way. Save it to the server the first time took minutes. If I saved it to a local drive it was fine. I tried everything from a previous post I blogged and nothing worked. Another computer at our store also had the same issue so I knew it was not just my PC. I finally found a solution on the web. Changing my drive map from a NetBIOS to a FQDN mapping. Actually my old drive map was \\SERVER NAME\SHARE. I changed this to \\FULL DOMAIN NAME\SHARE (ex. net use h: \\server\share to net use h: \\domain.local\share)
NetBIOS reference (e.g. \\DOMAIN\DFS\Share) to a FQDN reference (\\corp.domain.com\DFS\Share).
I found this from this website and this site. Others find the reverse fixes their problem.
AMMENDMENT:
After a little while it was still giving me issues even with the above changed. I think I now found the solution.
If you are running Windows 2008 as the server and running Windows Vista or 7 as the client then SMB2 can be causing the issue. Disable SMB2 on the server by doing the following:
Add a REG_DWORD entry named Smb2 with a value of 0 to
HKLM\System\CurrentControlSet\Services\LanmanServer\Parameters
Then restart the server. Reference if from this blog
Also information on SMB2 can be found here.
Thanks for this, I was having the same issue. Mapping the drive with the FQDN of the file server did the trick.