Networking

[PanzerI]

I currently have a computer downstairs connected to a modem which is then connected to a wireless router. In my upstairs I have a second computer connected also to the wireless router through a RJ-45 cable. I have beside my upstairs computer a wireless laptop. I cannot network my upstairs desktop with my laptop. It shows up but says that we do not have the access rights. Anyone please help?

[bAdWaYz]

What ver of Windows do the computers use that you are trying to share file/folders between? Also do those computer have any sort of firewalls that might be running?