Problems might be related to Sasser Worm....
"they believe that the problem may be the incredibly swift proliferation of the Sasser.Worm.
This is a new threat only identified in the past few days by the AV community and is still under investigation as to the exact effects.
Systems Affected:
Windows 2000, Windows Server 2003, Windows XP
Systems Not Affected:
Linux, Macintosh, Novell Netware, OS/2, UNIX, Windows 95, Windows
98, Windows Me, Windows NT
The above list should be treated as a preliminary list due to the short period of analysis so far on this threat.
** DETECTION PROCESS **
To detect the presence of this virus please do the following:
Close all applications running.
Get user to press CTRL+ALT+DEL and switch to 'Process List' tab.
Check for the presence of a file named 'avserve.exe' in this list.
** REMOVAL PROCESS **
If they have other working internet access send user to:symantec "
http://securityresponse.symantec.com/avcenter/venc/data/w32.sasser.worm.html