Vista - Remote Desktop Vista Ultimate SP1 host

I've got a new PC installed with Vista Ultimate SP1. I've set up remote
desktop and can connect to the PC remotely. However, if I log off, I'm never
able to reconnect to the host because the Vista host hangs at the Welcome
screen. I can always see the user account choice screen, but as soon as I
log in I see the Welcome message and the "spinning cirlce" runs forever.
Even if I try to log on locally at the Vista PC, it hangs at the Welcome
screen and I have to power off/on to get control of the PC.

I've tried connecting from multiple PCs and still have the same problem.
I've created a new user account and get the same problem.

Any ideas?