If the DVR has a 4-pin RS-232/TTL header on the board:
Before trying technical resets, try these quick checks to save time: raysharp dvr password reset
Check for a Master Password: Some older Raysharp models utilize generic "master passwords" used by technicians. While these change frequently, a common one for older firmware is often 123456 or adminadmin.
If those didn't work, move on to the methods below. If the DVR has a 4-pin RS-232/TTL header
For a button: Press and hold it while powering on the DVR. Keep holding for 10–15 seconds until you hear a beep or see all LEDs flash.
For jumper pins: Short the two pins with a metal screwdriver or jumper cap, then power on the DVR for 10 seconds. Remove the short.
Power off, reassemble, and power on. The default credentials will be restored: