Uniden dect 6.0 deregister all handsets - Uniden DECT 2080-5 Quint Phone

SOURCE: Resetting the Handset

YOU might need to deregister the hand set first by holding down the red end (hang up key) and keep it down while holding the # key. If deregister wont work use base unavailable and yes, you are sure twice.

List the handset numbers of those working handsets
Using a WORKING handset follow these directions
Resetting Handsets
If you want to register the handset to a different base or
replace a handset with another one, you must first clear the
registration information from the base and the handset.
1. Press and hold [ ] and [#] for
at least 5 seconds, until the
SYSTEM RESET menu
appears.
2. Select the DEREGISTER HS
submenu. WHICH HANDSET?
appears in the display.
3. Move the cursor to select the handset ID to be de-registered
from the list, and then press the OK soft key. DEREGISTER HS
appears. CHOSE A NUMBER THAT IS NOT ONE OF YOUR WORKING HANDSETS
4. Move the cursor to select YES, and then press the OK soft key.
When ARE YOU SURE? appears, select YES. You will hear a
confirmation tone.
PUT THE HANDSET IN THE BASE CHARGER AND IT SHOULD REGISTER

Hope This Helps - It worked for me

SOURCE: How to turn off telephone ringer on handset for

Just press the down arrow on the center button

SOURCE: uniden dect 6.0 display reads searching

Hi there, try this. Press and hold th eend key on one of the handsets, while holding the end key, press and hold the # key. After 3 or 4 seconds tha thandset should beep and read deregister Handset and underneath that "Base Unavailible". Select base aunavailible and confirm. Then tha thandset should read "Handset not registered, place handset on base" Once you place the handset in the bace cralde it should register in 5 - 10 seconds or so. then you should be good to go.

SOURCE: Reset base unit of Uniden TRU9485

Uniden TRU9485 (This didn’t work for me but this was the first instruction from Uniden Tech Support)

TO RESET THE BASE UNIT:
Unplug the base unit AC adapter.
Hold down for 15 seconds the DND, * and “menu” soft key (the middle silver soft key under the LCD) while plugging the base unit AC adapter back in.
All the settings should be reset.

Uniden TRU9485 (Worked for me)
ALTERNATE WAY TO RESET THE BASE UNIT:

Unplug the base unit AC adapter.
Hold down for 15 seconds the DELETE KEY (zero with a line through it) while plugging base unit AC adapter back in.
All the settings should be reset.

SOURCE: how to deregister a handset without the base with which it orginally registered

Uniden TRU 8888Handset Reset (De-Register): 1. Remove Battery. 2. Reconnect battery while holding down "*" and "#" key. 3. Then press the right upper soft key under the LCD. 4. Press the "End" key. 5. Phone will be ready to register to the base.