My HP 2210 has the same problem. Powering it off hasn't helped in the last few weeks, so before I toss it I figure I could perhaps open up the machine and help it with it's problem that it really created by itself, out of the blue!
As it's all plastics and hardly any screws, I can't open it without destroying the casing.
I'm going to trash it as well, and make sure I don't buy another HP printer, and advise anyone to do the same thing as well. I don't like machinery that has a life of it's own, and in this case quite a self-destructive one!
Roloff, June 2007