Vista can see Win 7 in Network - how come 7 no see vista?

I need to set up a network for file sharing between my Win 7 system, and my Vista machine. (If I can include my partner's Mac, that would be the best)

All computers are on the same wireless network - Win 7 has direct ethernet. All use same network printer.

So far, I cannot get 7 and Vista talking. Vista can see 7 and printer, as well as itself in Network. Win 7 only lists itself in Network, not even printer (which it uses daily)

Both have WORKGROUP as default network.

Thanks for any help!

Thanks for the response Roderunner.

a) These are both my computers, so there is no security issue whatsoever. If at all possible, what I really want is full access connectivity, not just access to a shared folder.

b) I tried the changes suggested in the pdf, and here are the results:

• I can now see all computers in the network lists on both machines.
• In addition to the expected systems and printer, in both machines I see an object I am not familiar with, under "media devices" which is labeled the same as the win7 machine. When clicked a WMP opens.
• If I click on the win7 machine from the vista, it says it is not accessible, might not have permissions.
• If I click on the vista machine from in the win7, I see what appears to be an empty folder. However when I attempt to drop an object into the folder, it does not appear in the window.

Any more help appreciated.