Sounds like the guy got hit by some unpatched Internet explorer exploit, or somebody else used his computer. Either that or black magic.
nothing black magic about making internet explorer resistant to exploits as this bourn person says. i have been reading up on how it can be done on wilders in the last few weeks. like you i and many more i did not think it could be done but it has been proved to my amazement it can be done and it works. if you take a little time to find the details and do it you will be extremely safe as you never have been.