If you hav'nt yet tried... Uninstall the vid card drivers, and let windows find a suitable driver.
I seen a similar problem with a 6600GT, and that fixed it, though I dont know what version windows found and installed.
Thanks simmons2, You've saved me a whole lot of pain trying to work out what this problem I was having.
Another way for a temp solution is to ZIP or RAR the files, this works fine.
Also, I mailed Kaspersky, and they said around a week.
Cheers
Kev