Most of the Computers very slow suddently

in my office all of sudden today all the computers are very slow at opening word/excel files ..

i thought it was a network problem coz all our user files are on the server but then I found that it was doing the same for local files ...

I thought it was something to do with Norton AV 2003 definition files ... but then when I looked around two of the machines have older definition files ...

on my own workstation I uninstalled the AV and it works like a charm now ... but obviously i just cant uninstall all AV's

what could be the possible cause ?

thanks for all the help ...

OS : WinXP Pro SP1
Office : Office XP SP2

As a test, replace Norton with Grisoft's AVG Anti-Virus on one of the machines and see if it makes a difference.

I had a couple of NORTON Corp 8.1 machines infected with the Welchia virus. The Autoprotect shield was apparent on the taskbar, but if you tried a manual scan, it wouldn't start.

The effects were across the WAN performance problems. Also, my firewall crashed when the log filled up with PING requests.

It is a problem with Norton:

http://discussions.virtualdr.com/sho...hreadid=154142

http://discussions.virtualdr.com/sho...hreadid=154140

http://discussions.virtualdr.com/sho...hreadid=154192

two very simple workarounds :

1. disable office plug in

2. disable check for Publishers's certificate revocation in IE (under Tools > Internet Options > Advanced > Security

thanks for the help guys ... I hope we have a patch from symanctec/verisign soon...

lets sue them !!!