How do I deregister a lost phone on a vtech 6529?

SOURCE: Deregistering a phone you can't find

I had trouble deregistering one of the phones, as it has to be close to the original base (kept telling me out of range). I found out that pressing END and #, also deregisters.

SOURCE: Vtech VT 2656 2.4GHz

Was looking for this for awhile as well, if you held onto them like I did the wait paid off, they must have put this up since I last looked.
http://www.vtechphones.com/vtechui/support/faq_problem.cfm?model_id=F0D43FC0-19FE-4ABD-BC22-C1306B1EC90A&type=problem&parent_id=133

SOURCE: nEED TO DEREGISTER LOST HANDSET

The "END" and "#" key combination can be used for several purposes:

1) If wanting to use an ALREADY REGISTERED HANDSET on an alternate base, and if if the INITIAL BASE isn't available to deregister the handset:

1a) Press "END" + "#" until it for 5+ seconds (wait for it to beep)
1b) Choose the "Base Unavailable" option
1c) That'll deregister the CURRENT HANDSET so that it can be re-registered on ANY base.

2) If a BASE has a handset registered to it which you no longer want registered but the registered handset is missing or broken:

2a) Grab another WORKING handset which is properly REGISTERED to the BASE in question
2b) Press and hold the "END" + "#" key for 5+ seconds (wait for it to beep)
2c) Choose the "Deregister HS" menu option
2d) Pick the REGISTERED HANDSET # to de-register. (Every other registered handset EXCEPT THE ONE YOU'RE ON will appear in the list!)

SOURCE: I need to deregister all the handsets from the vtech i5867 base unit

My hand held still says "Searching for Base"???

SOURCE: I need to deregister VTech Phone model CS6329-2

on handset, press talk/FLASH, then press OFF /clear.