If the above defaults fail, the DVR may have been locked out or the password is a randomly generated string based on the current date. This is a security feature found on many generic DVRs.
Q: How do I change the default password on my DVR-208G-F1? A: To change the default password, log in to the device using the default credentials, navigate to the configuration menu, select the user management option, and enter a new password. Dvr-208g-f1 Default Password