WinMORE will only allow you to have one Active record for each associate. If you get the error message that "The SSN/SIN is also used as the SSN/SIN on associate XXXX", then the record indicated by the last 4 digits of the MORE ID in the error is still active in WinMORE. In most cases this occurs when you try to add an associate back to your market center and their prior record is VR.
Click here for instructions on re-activating a VR associate.