in which windows vista tries to kill the portable gis idea

Well, there was I just working away in the office, on my super-cool portable GIS setup, doing some work on a postgresql-driven database all working nicely on the USB stick. I should say that this has been working just fine in both my home (Vista) and office (XP) environment for months now. Time came to head off home, so I stopped everything, ejected the stick nicely, took it home and went to start working on it again… only for postgresql to refuse to work.