I have 3 computers networked through a Linksys router. Two are wired and 1 is wireless. I used to be able to view files on the other computers by going to the shared files folders. I now can only access the computer that's connected wirelessy. I can still connect to the Internet with all computers but when I try to access the two that I'm having problems with I get the message: \\xxx-xxx\shareddocs is not accessible. You might not have permission to use this network resource. Contact the administrator of this server to find out if you have access permissions. Not enough server storage is available to process this command.
Problem with the memory was that I ran out of time. I work freelance and had to get on with some work. It's a pity that these problems take so long resolving. I can't recall having made any user account setting adjustments.
What OSs are on the 3 PCs? You might have to run the Network Setup Wizard again. RE the SPs it will say under System Properties what you have. I also have this problem and its intermittent (linksys as well!). Bugs the hell out of me. A router reboot, with the 3 PCs on, usually cures it for me.