There are many threads here with problems similar to this one but I havent found one this confounding. 3 computers on the network. Two XP Pro SP3 machines and one Windows 7 Home Premium machine. Call the XP boxes XPa and XPb. I cannot access shares on XPa from 7 but have no problem accessing shares on XPb. Same username and password on all 3 machines, all are admins on respective computers.
From 7 to XPa, it asks for username/pw, enter it and access denied.
From 7 to XPb, it asks for nothing, can open XPb shares without problem.
From XPa to 7 it asks for nothing, can open 7 shares without problem.
From XPb to 7 it asks for nothing, can open 7 shares without problem.
From XPa to XPb it asks for nothing, can open XPb shares without problem.
From XPb to XPa it opens a 'connecting to' window with the username grayed out which is XPa\guest. But when opening a mapped drive from XPb to XPa, it asks for credentials for \\XPa\share. Once again, I use the only username/password combo there is without success. I compared the local computer security settings on both XP boxes but did not see any differences.
Accessing XPa shares from 7 is what I really want to do. The rest I included to provide all the pieces.