Can't Backup to Specific PC

Attempting to select a PC w/ a MyBook Passport drive as a destination (which is set to share w/ proper permissions) for the MyBook Live backup, but entering Guest as the username and leaving a blank password gives me the following error:

Now typing my account name and password, I don’t get the error but then the shares do not show up (it says there are none). Just tried from several other machines in the office and some laptops and they all can see the shares fine, it’s just the MyBook can’t see it. Athough, the MyBook can see shares from other PC’s (not mine)… How can I fix this?

Update: Rebooted the MyBook and router, now I see my workgroup name listed as two seperate entities (??) (workgroup name is NGMI) and see every other device on the network but my desktop (from only the MyBook).

The workgroup name needs to be the same in the computer and MBL 

Unfortunately making it on the same workgroup as every other PC didn’t change anything. As far as I understand anyways, workgroups are more for organization more than anything… and I was able to see other PCs beloning to NGMI when the MyBook was ‘WORKGROUP’ but still can’t see D0001 even though both are now on NGMI  

 :S

Well now I’m trying to use the routers USB port and backing up to an external plugged into that, and I get  36102  - Your safepoint could not be created due to a failed request. Please try creating your safepoint again.

Update: Rebooted the router, external + NAS then used the router to format the external, now the NAS can make a safepoint on the External via the router’s USB port but the transfer speed seems to be going slow. The NAS must be backed up every friday and taken off-site… hopefully the initial backup is done by Monday then subsequent backups are < 1 hour.