Sharp Line 16CH DVR default password or how to reset it?

[Cypaubr 0]

Hi everyone,

I recovered an "old" Sharp Line 16CH DVR from the junk, everything seems to be working except the fact that it asks me a password for some actions (like Menu, Search or Shutdown). I have no further info about the model (no printing on sticker on the case) but it's branded Sharp Line and there is "KDVR-1160 REV 7.1" on the motherboard. Anybody knows the default password or how to reset it? Here are some pictures of the DVR:

Thanks for your help!