You know you forgot to create an account of said name on the server.
It's an old thing many forgot. Try that first.
I have a windows 7 PC connected to other Win XP computers on a home network. I have shared the Win7 computer and the other XP computers. from the win7 computer I can see and open files on the XP computers, but from the XP computers, I can see the drive in view workgroup computers but when I try to open it, it says connecting to and asks me for a username and password and when I enter name and password it does not connect.
However from the win7 pc I can see and open the drives on the other pcs