Huge sudden slow done and download problems with PC

[lizsaunders]

Hello,

Can anyone help. 2 days ago, my computer suddenly slowed down to snail pace ...!!!
We've run a virus check and can't find anything, but the PC will npt allow us to update our anti-virus either. If we run a programme it takes an eternity to load up, as does the internet, and evrytime we click on something it has a huge delayed reaction. Basically it's like our PC has just walked out of the 1980's. We also keep getting the 'this programe is not responding box'. I defragged the C drive but this made little or no difference to the speed. Could it be a virus not picked up by our anti virus.? or memory problem.? Thanks in advance for any suggestions.

[Suspishio]

OK - saw your post above. Thanks

Have a read of the first three sticky posts at the top of this forum and then report back with the inputs we need.