network nightmares

We run a 10-workstation Novell 3.2 network. Suddenly, some of the workstations are reponding very slowly when pulling data from the server. Others are working just fine. I haven't made any changes lately, other than update our DAT files for Viruscan, which I did to all of the machinces the same day. Everything ran fine the day after I did the updates, so I don't think it's that. Thinking the meomry cache on the server needed to be cleared, I rebooted, but it made no difference. I've powered down the network hubs (we have 2), and spaced them out (before they were stacked, with the DSL modem on top, and seemed to be getting hot). They've cooled off, but there's no difference in speed. The slow machines are not all on the same hub, so it's not one hub going bad. The server's hard drive is only 50% full, but I deleted as much extra data as I could anyway. I thought maybe it had to do with network traffic, i.e. those who logged in last might be running more slowly, but the person who logged in #1 today is having problems, and person #2 is fine. I've defraged & run disk clean up on the worst machines. The amount of memory doesn't seem to matter - some of the 32 MB machines are running fater than the 64MBs, and vice versa.<:LINEBREAK:><:LINEBREAK:>I'm trying to check the Novell support site, but they seem to be having problems.<:LINEBREAK:><:LINEBREAK:>Please help, if you can. Any suggestions would be appreciated!

There are a couple of things I can think of that could be causing it. The first would be that that the workstation that has slowed didn't get a dat file update but instead got a superdat update. When that happens the Mcafee engine is also updated which is not compatible with versions of Novell previous to version 4x.

The second thing would be with moving the hubs around that the network card is set to full duplex and has been connected to a regular hub connection that doesn't support full duplex. Sean¸

Do you know anything more about which version of VirusScan and the engine won't work? We're running VirusScan 4.0.3, with the 4.1.40 scan engine. I'm not sure if I ran the DAT or SuperDat this last time - I know I downloaded both at some point. I checked McAfee's and Novell's websites, but couldn't find anthing specific. I have an e-mail in to McAfee's tech support - I'm not sure how quickly they'll respond.<:LINEBREAK:><:LINEBREAK:>I did switch one cable when I moved the hubs - it was the short one that connected the two together. (one hub is connected to the other hub, then that hub connects to the server) I'll try to switch it back, if I can remember which two plugs I swapped, but the slowness stared before I even touched the hubs.<:LINEBREAK:><:LINEBREAK:>Thanks for your suggestions - let me know if you think of anything else.

The latest available Mcafee engine is version 4.1.40. So you likely did upgrade the engine as well. As far as I know it's not a problem unless Netshield is installed(The 4150XDAT.EXE utility does not support VirusScan for UNIX software, GroupShield Notes software, or NetShield NetWare software.---Some McAfee anti-virus products, such as NetShield for Novell NetWare, cannot use the executable<:LINEBREAK:>version of the .DAT file update. Instead, you must<:LINEBREAK:>copy .DAT file updates directly to the product directory.)

The 4150 .DAT files are compatible with McAfee anti-virus products that use any 4.x.xx scan.(These .DAT files will NOT work with v3.x or v2.x scan engines.)

McAfee recommends that you upgrade to the latest version of the v4.x.xx engine for optimal virus detection and repair.

Hope this helps, Sean