To register an ELX500, TCX450, TCX440, or TCX400 handset, follow the steps below:
Disconnect the AC adapter from the main base.
While pressing down find hs, reconnect the AC adapter.
On the handset, press and hold # until you hear a beep.
While the handset is registering, Handset Registering will appear in the LCD. When Registration Complete is displayed, the handset has been registered to the base. If Registration Failed appears, please try these steps again.
De-register the Handset
Deregister the handset's ID from the main base unit or the base ID from the handset. You will usually only deregister the handset if you are moving it from one base to another, if you are having a problem with your phone or if you need to change the digital security code. The digital security code is an identification code used to connect the handset and the base unit. Normally, setting the code is not necessary. In the rare situation that you suspect another cordless telephone is using the same security code, you can change the code by de-registering and reregistering all handsets.
1) With the phone in standby mode, press the MENU soft key on the handset and select Deregister HS. Then, press the OK soft key. Deregister HS? appears.
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2) Press cid/vol/
to select Yes and
then the OK soft key.
When de-registration is complete you will hear a confirmation tone, and Deregistration Complete appears. 3) After de-registering the handset, place the handset to the base to register. You must re-register the handset before you can use it.
 EXPANDING YOUR PHONE
EXPANDING YOUR PHONE