I was having the same problem. Old computer was XP, New computer is Win7.
First try no go. Checked File repository settings. Had the old user Login name in - changed to the new/ correct user name.
All the rest was correct (I had made a share in the Win 7 machine exactly as in the old XP, same domain name and all.
Tried a bunch of different things as suggested, nothing worked. (Did not upgrade firmware - still using 20.105.01.010)
Did not do full memory reset either. But tried entering the full user name path (complete with WORKGROUP, which is the correct name) and creating a new user account on teh computer just in case it needed to be a simple user account, not an administrator account.
In the end, I turned off the xerox machine, and back on, still no go.
Turned off the computer, then back on, and SUCCESS!
I should have known better! should have done that right away after I changed the "Login" name on the Xerox File Repository setup, which was the only thing that was clearly wrong. Even though
I can not see here why it would need that, I have seen many cases before where this is nonetheless necessary.
Also, sometimes the Router can take its time to workout the necessary authorizations to new user/ requests. Allowing a few minutes between changes, before testing, can make a big sifference. Otherwise, one just ends up going over the successful fix without giving the hardware/ software time to adjust/ reset. The funny part is, even though I know this fully well, I still end up getting caught all the time.
Cheers,