I don't see a hardware-method to reset to factory either... only under Main Menu > System Function > System Maintenance > LOAD DEFAULT. But you would have had to log in first.
I seem to remember reading that one of the default passwords was all 1s (e.g. 11111 or 111111). You could try those, or try variations on the password you tried to use, in case the cumbersome, on-screen interface caused you to miss a character. Looks like it is a maximum of 6 characters.
Manual states a support number of: 1-800-444-3353 and I know they're currently only available during regular business hours.
The whole Bunker Hill security line is just garbage! Whoever designed this piece of garbage should be shot. In their whole "users guide" They don't even mention passwords, much less the difference between a user and an administrative password. So when you pick a users password then try to set the time or anything else under the menu, it gives you a message that you don't have the authority to change anything, so you can't set the time or anything else. No wonder they sell the units for so cheap. They're just knowingly ripping off everyone that buys one and their 1-800 help line is just a big joke. First I called the listed number who asked for the item number the gave me another Harbor Freight 800 number to call and after being on hold for 10 minutes they told me to leave my number and they would call me back. Corporations such as this are evil and are whats killing the world!
Called the 2nd 800 line and was given a procedure on resettig the password to the default admin password.
Do you remember what the procedure was? I can not get a hold of anyone at either 800 #!!! There tech support sucks!