IPP Printing in Vista

> Our print server is a 2003 Server R2 w/ SP1 box that is part of our domain
> and is running IPP.
>
> We have loaded Vista up on a workstation to test printing functionality and
> are running into an issue.
>
> Users navigate to our printer url and choose the printer they wish to
> install, click on "connect", and are prompted "do you want to add a printer
> connection to htttp://kssnchqfspsp00/printers/02cl7000clr/.printer?"
>
> We click "yes" and are prompted with "to access this printer, you must enter
> a user name and password".
>
> I have entered my domain credentials and when I press OK I receive the
> message "Printer not found on server, unable to connect".
>
> This appears to be only related to IE7 on Vista, as I have loaded IE7 on an
> XP box and have no problems mapping the printer. IE7 or IE6 on XP never
> prompt me for my network password when trying to map a printer via IPP.
>
> Now I can browse the directory for printers and map them that way on this
> Vista box - but it appears that somewhere the permissions might be too strict
> to allow the mapping of printers over IPP with Vista.
>
> Anyone have any ideas why I would be getting prompted for network
> credentials on a Vista box with IPP?
>
> Thanks in advance.
>