Vista - Printer doesnt stays as default

hi you all

i wrote about the same to an older post. but i thought now i open another
new, because the problem still persists. We are using Windows Vista
Enterprise 32-bit. Windows 2003 Printservers and Printers from different
manufacturers.

We only have network printers in our company, the only local printers are
the MS XPS Printer, the Adobe PDF printer and a Snag-IT printer.
Anyway, i can add network printers without having troubles and i can choose
the default printer too. but if i reboot i can only set one of the local
printers like the XPS as default. Setting a network printer as default will
no longer work.
but if i add a new printer, im able to set THIS printer as default until i
reboot the first time. After a reboot, the default printer is resetted to
SnagIT and i can only set the local printers as default. and if we dont
install SnagIT the default printer is the XPS printer.

I used a lot of time troubleshooting this issue. but its so anoying because
it doesnt happen on every computer in our network and it also doesnt happen
at the same time. and not every user on the same machine does have the
problem, so its user specific.

we found out, that if you delete the affected userprofile in the control
center the problem is solved for a while. but another irregularity is, that
the problem sometimes occur after the machine was set up and sometimes after
a user worked with the computer for some months.
So im asking me what could destroy the userprofile oder the user specified
registry?! and i have no answer until now.

another solution
(http://www.microsoft.com/communities...xp=&sloc=en-us)
is to rename oder deactivate any local printer or rename the network printer.
but I think thats probably a solution for home users but not for big companys
with lots of printers.

so do anyone have an idea how i can get around this problem?

thank you in advance

-Will