I have a few users who got new machines with Win7 Pro and everything seems to be going well with the exception of this print issue.
They print to a network attached HP 4350 PCL6, and have done so for 5 years on XP. The printer installs with no problem and can print fine. the issue comes when trying to set it to default.
when you log back in it sets it to the next logical local printer as default, in this case a quicken PDF, i even deleted that and it just went to the adobe PDF so it does not seem like a program setting. As I've also done selective startup with no startup programs on and it still does it.
I checked the logs and event 823 comes up and states in the details that the print spooler is setting this option. When i set it back manually i see the data option as "0" instead of "1"
It almost seems like it tries to load the network printer and because it's just logging in it can't see it then chooses the local PDF instead.
These are also desktops with only one network location configured so it's not a location aware based problem.