Opticon H21 Hard Reset
First remove the back lid and the battery and return the lock that keeps the lid in place back in the position as if the back lid would be on. Then keep both the POWER + Capture + End keys pressed while inserting the battery.
Power key = the red key on the top of the device. End key = the key with the red phone icon on it. Capture key = the one on the right side of the end key, It has a camera icon on it.
If performed right, the device will shake and boot the white start-up H21 screen. After a few seconds you get a Warning message, press YES to clean boot:
– for H21 numeric keypad: use the button that’s above the F2 key for YES and the button above F3 for NO;
– for H21 qwerty keypad: use the button that’s above the F1 key for YES and the button above F2 for NO.
For more information download the Manual