Sometime in September my laptop (it's an HP) decided it didn't want to play media files any more. iTunes wouldn't open, WMP froze my computer, not even streaming sites worked, it was a mess. So after reinstalling a bunch of things in all kinds of convoluted ways, I contacted the live chat support on the HP website.
I had to try four times, because I could not get anyone who was any help. The first three people I talked to all told me to reinstall iTunes, even though I explained quite coherently why it wasn't an iTunes problem and that I'd reinstalled about three times already.
The fourth guy was my favorite, though. His solution to the epic system failure throwing up errors all over my computer? Disable error reporting. This didn't do much good, either.
(ps: in the end I had a friend look at the computer. He figured out the problem in about five minutes.)