marko - I did mean to reply to your post on the weekend - but was under suspension at the time.....
that homepage set to "blank" is the telltale sign of a mob called www.coolweb.com setting up spyware on your machine.
the 'coolweb' spyware is probably the hardest to get rid of, it really is persistent. My solution was to reformat the hard drive and reload everything.... so if you've got a few days....
there is a program available called CWShredder but I don't know how effective it is - one of the problems with 'coolweb' bug is that there are many variants of it...
anyway, you could Google 'coolweb' I'm sure there are plenty of solutions that people have posted.... bad luck...
and if you are surfing the net, set your IE security to the highest value, that way you'll avoid most of the worst....
