@jabyano.. Problem is that of all the live tile apps I have tested, and that's about 12 so far, only Flixter reliably removes the key from HKLM/Software/Microsoft/PushClient/Endpoints registry key, when you disable the live tile feature and/or delete the app. None of the other apps I have tried disabling or deleting remove this key. Plus as noted, some apps create an additional key when they disconnect and then later reconnect when you open the app. When Endpoints reaches 15 entries any new installs/reconnects will not work any longer.
I hard reset my phone to test this and paid to dev unlock my phone to research the registry. With 8 live tiles, my Endpoints registry key gets up to 15 entries within a week or two because of apps adding additional entries. All I do is delete the Endpoint key and everything starts working again till the next time the contents of the key builds up.
If you don't have a way to dev unlock (using Chevron for example) you can't access the registry, so a hard reset is the only solution to getting your live tiles back. I can tell you MS is looking at this but a fix could take them months. I am trying to find a dev who will create an homebrew app to delete this key. Want to submit it to Marketplace knowing it will be rejected but then call Microsoft out on this. They need to address it now. Sorry the news is not better. Hard reset sucks but my phone is actually working better since then. I have deleted the contents of this key a half dozen times in tests and all my tiles are working. I have a Surround but this has also been done successfully on an HD7 and Focus so far.
Sent from my HTC Surround using Board Express