Small workgroup of Windows PCs has been configured with a Win 10 PC as a file server for the workgroup. I provide as needed support. No issues for over a year. Suddenly this morning when a Windows 7 pro user attempted to connect the share had a red X. I tried to disconnect the mapped drive and reconfigure it. I got the error "The network folder specified is currently mapped using a different user name and password". I verified that the mapped drive had been disconnected using Net Use, nothing listed. I verified that the folder is shared on the Windows 10 PC. I verified that Advanced file and printer sharing is configured correctly. I also tried two other solutions in a google search, a registry hack and adding the mapped drive by IP address, neither solution worked. I can ping the file server by name and by IP address. The Windows 7 PC was not in a homegroup until this morning. I removed it from the home group and restarted but error persists. The shared folder is \\fileserver\Users\Public\Documents, it appears in explorer as a share named \\FileServer\documents2. I've tried a couple different user credentials on the file server when adding the mapped drive as "other user".