Trouble mapping folder from Vista 64 to Win7 64

Good afternoon everyone, hoping to get some help here. I just acquired a Gateway laptop with Win7 64 Pro, and for some reason I cannot for the life of me get it to map a folder on my Vista 64 Ultimate desktop. I can connect to the public folders, but I cannot connect to my private user folders. I have another laptop in the house running Win7 32-bit that maps just fine, and also I can go from the desktop to the Gateway with no issues. The only problem I have is getting in to my private user files. Whenever I try to connect to one, I get a message saying I dont have permission. I can get to \\mediapc where I can see the shared folders, and I can get in to \\mediapc\public with no problems, but if I try to get in to \\mediapc\users, for example, I get that message. Again, I can get in to it just fine from my 32-bit Gateway laptop.

I have tried turning off both firewalls at the same time with no luck, so I know its not a firewall issue on either computer. Does anyone have any other ideas? This is my first time asking for help on here, so if I need to provide screenshots or anything please let me know. Thanks!!

Between Win7 systems you share any folder via Homegroup. Vista systems cannot participate in that luxury. You have to go via the public folders.

I am not trying to share via Homegroups, I am trying to do basic drive mapping and folder sharing. I am already sharing folders on the Vista PC with a Win7 32-bit laptop. However I cannot share those same folders on another Win7 64-bit laptop I have.