cannot view files on one pc on network

I have a network set up on with two pc?s one is connecting through a linksys wireless router and the other connects to the same wireless router by direct cable. The router connects to the modem. The pc?s all show up in the network on both pc?s but the one that?s wireless give the… (You may not have permission to connect, ask your administrator etc.) When trying to view files on the wired PC. I have all the firewalls turned off and have checked everything I can think of. What can the problem be? I have shared files set up on both units and file sharting is turned on. The wired pc allows me to view the shared files on both pc?s in the network.