De-register Vtech IS6200 headset from CS6919 base and register the IS6200 headset to Vtech DS6621 base.

SOURCE: How to I reset the base for a Vtech VT-2431

This worked for me after lots of digging....If you have already tryed reregistering your handsets and can only get two-or three to work try this and deregister them and re-register. If your base model number is vt2431: Take the handset out of the base, press **335782 on the dial pad of the base. (do not have the line active or anything , just put the (2) stars and 335782 in (no spaces) on the base unit. This will de-register all of the handsets at one time. Then just re-register the handsets...

Testimonial: "This works perfectly!!! I don't know how you found it, but GREAT JOB!!! THANKS!!!"

SOURCE: Vtech CS5113 won't show on headset or base there is a new message

I have a CS5113 new 5.8GHz phone. It was not using some time. After that when i plugged , charging led is glowing on phone. it was charged 16 hours. but no display on phone. Please suggest the remidy.

SOURCE: How do I deregister my handsets on my VTech 2656

To be able to register your replacement handset, you must de-register all the handsets from the VT2656 base unit.

Follow the steps below to de-register your handset(s) from the VT2656 base:

1. Take out the handset that sits on the base.
2. Unplug power from the base.
3. Hold down PAGE while reconnecting power. When the In Use light blinks, release the PAGE key.
4. Hold down PAGE key for 5 seconds. When the In Use light begins to flash, release the PAGE key.
5. The handset charging light will blink 5 times. Within 5 seconds from when it stops blinking, press PAGE once.

You must register the handset(s) by following the steps below:

1. After charging the handset, remove it from the cradle, the LCD display will read "SEARCHING FOR BASE".
2. Press "NEW" and then enter the 15-digit Base ID code, located on the underside of the VT2656 base unit.
3. Press "OK". The handset will display "PLEASE WAIT!!".
4. Wait approximately 15 seconds. The handset will display "FOUND BASE". If the handset displays "BASE BUSY TRY LATER", this indicates that the system is in use. Wait until the base unit is in the idle (on hook) mode and repeat steps 2-4.

SOURCE: How do I de-register the

To de-register all handsets

1. Press and hold HANDSET LOCATOR on the telephone base for about 10 seconds (until the IN USE light turns on and starts to flash), then release the HANDSET LOCATOR button.

2. Immediately press and release HANDSET LOCATOR again. You must press HANDSET LOCATOR while the IN USE light is still flashing. (The light flashes for about seven seconds. If the light stops flashing, pick up the handset and place it back into the telephone base, then start again with step one above.)

3. The handset(s) will show CONNECTING... and it will take about 10 seconds to complete the de-registration process. ALL handsets will show NOT REGISTERED if de-registration was successful.

SOURCE: how do you deregister vtech ds6401 handset without the base?

Enter the following on the handsets you want to deregister: *331734#, followed by the left soft-key (the key labelled "-" at the top left of the keypad).