Okay - the run-down:
- Brought a new Dell rack-mount server up, running Server 2008 Standard x64.
- All Windows updates, File Services role added; everything completed without issue. Installed FS using 2003 and indexing option, not Windows Search Services.
- Installed Symantec Endpoint Protection 11.0.6000.645 (AV only - no NTP or email or anything).
- Robocopied all existing shares from the server (running 2003) and verified them on the 2008 rig (no issues).
- Deallocated and switched off the 2003 server; renamed the 2008 server to the 2003 server's former network name.
Shortly after migration, users complained of epic slowness. I changed the 2008 server to use WSS instead of 2003/indexing, restarting afterward. Still no joy. I've worked at it all week, trying different options out on the Internet-at-large.
THINGS I'VE TRIED (to no avail)
- Disabling SMB 2.0 on the server, leaving 1.0 active.
- Disabling SMB 1.0 on the server, leaving 2.0 active.
- Disabling SMB on the server, leaving neither version active (NetBIOS only, I guess?).
- Updating SEP to latest (11.0.7000.975).
- Uninstalling SEP altogether.
- Enabling/disabling IPv6 binding.
- Disabling TCP Offload at the NIC (both IPv4 and IPv6)
- Pretty much anything I found while hunting the Internets for solutionbeasts.
We have a mixed bag of clients, mostly XP, with some Win7 thrown in (all standard versions, pretty sure all are x86). I can open everything without issue, both from my Win7 (x86) laptop (my standard work machine) and from my XP VM x86 test machine (out on an ESX server). The only difference I can find (that seems like it would matter) is that my stuff is all on one subnet, while the other client machines are on another (x.x.1.x versus x.x.2.x).
I don't understand where the slowness comes from. Certainly, the 2003 server didn't have this problem or the users would've already complained. Any ideas or direction from the one community I trust to actually solve problems would be awesome.
And - I'll apologize in advance if there's actually a thread somewhere that answers just this issue; I just couldn't find it (but not for lack of trying). Thanks, in advance, all.