First, get to the latest firmware with this.
Then, if still failing go to the folder Properties > Sharing > Advanced Sharing > Permissions and actually add the user in, then , in CWIS, format the username exactly as it appears in brackets like this
If you are using Chrome, stop and use anything else, Xerox and Chrome don't play well at all with password fields.
While I fully understand it works on the other device just like you have it now, it doesn't matter, because the other device is capable of Windows Networking, and Netbios over TCP/IP. Connectkey products do not.