Deregister devices
If you want to replace a device, or reassign the designated device number of a registered device, you must deregister all devices that are registered to the telephone base. Then register each device individually.
To deregister all devices from your SN1157/ SN1196/SN1197/SN6146/SN6147/SN6196/SN6197 telephone base:
. Press and hold FIND HS at the side of the telephone base for about 10 seconds until the telephone base shows Registering... Please wait followed by Deregister all devices?, then release FIND HS.
. Immediately press YES or FIND HS.
3.All handsets show To register HS, see manual. The deregistration process takes about 10 seconds to complete.
To deregister all devices from your SN6127/SN6187 telephone base:
. Press and hold 
/FIND HANDSET at the side of the telephone base for about 10 seconds until the telephone base IN USE light turns solid red and then flashes red, then release 
/FIND HANDSET.
. Immediately press 
/FIND HANDSET.
3.All handsets show To register HS, see manual. The deregistration process takes about 10 seconds to complete.
You cannot deregister all devices if any system device is in use.