The buttons on the Advanced Functions screen perform the following functions.
Click Reset to reset the OT-21
Click Save User to save the user's current configuration
Click Restore User (Full) to restore all User configurations
Click Restore User (Partial) to restore all User configurations except IP addresses and related values, GPS position, and User list
Click Restore Factory (Full) to restore all factory default values
Click Restore Factory (Partial) to restore all factory default values except IP addresses and related values, GPS position, and User list