Two machines, 'A' and 'B', both running W7 sp1 x64, Both have the same username & password, Both are setup to share all drives, Both are using the hidden (or super) Admin account renamed (by design), Both can see one another, all drives, all folders, No firewalls. Initially 'B' could logon to 'A', but not the other way around. A search found the problem under Advanced Sharing. The 1st two entries were turned off. Now, 'A' can logon to 'B', but not the reverse which is opposite of what it was before. As soon as I try to connect, before I even type anything in, the message in the logon box is the above "Login failure". Nothing was done to 'B' where it initially worked before. Is this some one way deal, logon one way or the other, but not both?
Not sure if this is the reason, but maybe having the same credentials on both machines is confusing them - try changing the username at least on one machine
No dice, no difference. I read about that suggestion elsewhere and it didn't work. Over 10 years with 2k & XP and I didn't have this issue.
I normally set it up with fixed IP's since there are only six devices that use it, half only rarely. But, right now it's setup automatically since I haven't gotten around to change due to other changes in a on going process. But why would/should that matter? I never had a issue 'seeing' the other devices.
Your problem could lie here: You log on an Super Administrator, the Administrator account which is installed by Windows in default! That accounts differs from the 'normal' Administrator account and to have 2 or more 'Super' are logged in the same time, that could create an 'Conflict of Interest' and that would even 'forced' more in case auto assigning of machine IP's is used. Try to change either the name of the Administrator (and/or Password) to a different on each machine by maybe ad a number to it like 1 for the first, 2 for the second and so on and also use static IP's for every machine! While working with computer, never forget one fact: A computer isn't intelligent and also not perfect! A computer only do what you 'tell' to do with an logic defined by imperfect humans and therefore imperfect logic!