Two winxp desktops, Belkin wireless modem router able to share internet connection but not files or printer. Have read as many posts as possible on this matter here and tried many of the suggestions to no avail. Computers on same network and have different names, have enabled shared folders on both machines by going to properties, sharing.Firewall off and can ping both machines.
It applies insofar as you need to be logged into both with the same Username/Password.
If you have no additional User Accounts set up and your name was, for example, Andy Bell, Windows Explorer would be showing "Andy Bell's Documents" and in Documents & settings there would be an entry for Andy Bell. You are therefore logged in with the Username "Andy Bell" even if there is no Password set. In the "client" PC you need to be logged in also as Andy Bell so that the "host" PC recognises your login as a valid user of the "host" PC.
There are couple of ways that should allow you to access XP Pro. If the Username for the remote PC is Andy Bell and for the local PC is Billy Church, set up a new User Account in the remote PC with the Username Billy Church. The local PC logging in with the name Billy Church is then a valid existing user of the remote PC.
Alternatively, in the local PC, open "My Network Places" and from the menus, select "Tools > Map Network Drive". This sets up a "virtual" drive in the local PC which when opened is actually the shared folders in the remote PC. In Windows XP, when setting up the Network Drive, there is an option to "Connect using a different user name". This lets you specify the *CORRECT* login that matches the remote PC's one.