Vista Cannot Add A Shared Printer from XP (But Now You Can)
Seriously. If you want to print from a Vista computer but your printer is shared by another computer running Windows XP, then you need to hack up your XP registry a bit. Apparently, no one at Microsoft has yet come to believe this is worth fixing. The Microsoft recommended fix is just to install Vista everywhere, right? Well, that’s wrong. The less obvious (but more productive) fix is for XP.
For a point of reference on what number to land on…I went with 30 (values between 3-50 are valid on XP). The HP LaserJet 1200 (PCL) I was trying to share then worked like a charm.