Are they registered to a VSOM instance, and does VSOM still have valid access to the camera endpoint? If so, you should be able to set the password from the configuration page for the camera within VSOM.
If not, I don't believe there is any way to reset *only* the password. You may need to do a factory reset on the endpoint (reset button 15+ seconds).
Scott Olsen
Solutions Specialist
Bulletproof Solutions Inc.
Web: www.bulletproofsi.com