Troubleshooting - Cannot register a handset to a base unit. - Telephone

The maximum number of handsets is already registered to the base unit. Cancel unused handset registrations from the base unit.
Refer to your models Operating Manual for instruction on how to de-register a handset.
Check that the handset and base unit are at least one meter away from other electrical equipment to avoid interference when registering.
Models KX-TGB810, KX-TGB812, KX-TGB850, KX-TGB852, KX-TG2153 - Check that correct PIN code (default = 0000) has been entered.