Antivirus scan does not want to run

this is an old Toshiba laptop, pentium2 something with 64MB ram and 5GB hdd and win2k pro spanish

I never saw problems, but the owner told me that his running programs would sudenlly close and some wierd errors would appear.

I first made a spyware scan with ad-aware 6 with latest update, then I ran symantec latest virus removal tools [fixSbigF, fixDumaru, fixWelch, fixblast, fixwinsh] only found 2 (welch & blaster)

Then I installed Antivirus (below), SP4, blaster patch, IEsp1 and updates created after sp4

This person did have an antivirus, norton coporate 8, but never installed it (don´t know why..). After each installed updates I tried to scan with the antivirus, but after 8 seconds it would say the scan had completed, even in safe mode I get the same thing.

How can I make it work? I´ve never seen this problem, how about online virus scans?

*Updated Information*

I wonder if a full reinstall of the windows OS would fix his problems.

I was thinking the same thing, but what a hassle to get the drivers after reinstalling it.

A long time ago, some members posted online virus scanners that I have used once with success, going to do some search on the forums

UPDATE

I finally made NAV to display something when scanning

it begins to scan master boot record, then scans memory and poof! it stops there, says scan completed

I'd tried reinstalling NAV and no luck