Heyas,
I've actually solved this one with research (Yay, Google!!), but have spent many curious hours over many months pondering on how and why. Wondered if anybody else was (is) having the same problem.
I have an HP printer - one of those all-in-wonder thingies. An Officejet7310, with a "duplexer" on the back to automatically control double sided printing.
Some time ago, the printer suddenly started printing the reverse side of the documents inverted. The front side was one way up, the rear side was "upside down". Very odd.
I did manage to find an e-mail address of a guy who deals with the problem. If anybody needs it,
[email protected] sent me a patch, and installation instructions that would cover all brands of Vista.
Very relieved to have that one sorted - was a pain doing it manually all the time.