Vista Laptops Not Connecting To Printer

Hey, sorta have a general issue with my office.

All the wireless desktops connect fine whether its XP or Vista ,
But the Vista laptops always cannot detect the computer with the printer connected to it.
Another pattern i noticed is that the Vista Laptops cannot detect any of the XP desktops in general (including the printer computer as mentioned).
They seem to have no problem detecting all the Vista desktops.
So whenever i click ADD PRINTER or when i try to view the network from the Vista Laptops,
All i see are all the other Vista Desktops and Laptops.
On another note, XP Laptops are fine, they connect and detect to any of the two operating systems.
they print fine as well.

Please lend me your help as this is an urgent issue, thanks!

yes they are all the same workgroup
Security? if that's the case, please advise on how i may be able to fix this.
Thanks