Some examples of threads which already exist about this:
Do we get our contacts back?
Connection Error
Will NOT sign in!
Live! Messenger .. lots of bugs??
Unable to load contact list
Cannot sign in and no error message?
I very strongly suggest to read them, they answer your questions.
* The list you see in Windows Live Messenger is a cached list (this is a new feature of Windows Live Messenger).
It will be used whenever there are connection problems while WLM was retrieving your list from the servers. It is made that way so you could continue to chat with (some) contacts.
* Whenever the problems with the servers and the new protocol are fixed, Windows Live Messenger will be able to retrieve your full list again. MS is aware of these problems and is working on it, be patient...
* Problems with the servers can be local. And not everybody will experience the same problems; certain people will only see a "connection error" tooltip in the taskbar, others only see a blue or yellow notice on top of the contactlist, others have only half or even no contactlists visible, sharing folders might not work properly, etc... All these kind of things are the result of these server and new protocol problems.
* Certain Plus! features which deal with the contact list (like the Contact List Cleanup feature) get their information from Messenger. Thus if the information from Messenger is wrong (or rather: not up-to-date) then obviously those Plus! features which depend on that info will give you wrong or incomplete results also....
* Programs such as ZoneAlarm can cause connection troubles also.
* You could revert back to MSN Messenger 7.x by uninstalling Windows Live Messenger first. MSN Messenger 7.x works with an older protocol and may not suffer from the problems experienced lately in Windows Live Messenger with the new protocol (as much).
Why this is in bold? Because I have done nothing more than reporting threads all day long about this same issue. People, PLEASE
SEARCH FIRST BEFORE MAKING A THREAD OR EVEN A POST!
The list above with threads is only a small subset of what has been created about this issue. Many threads have also been simply deleted already by the mods...
So, please do not make multiple threads about this (hell, do not make multiple threads about any subject for that matter, 1 existing thread is enough). Always search before you make a post or thread!
To others, if you see such duplicated threads, PLEASE do not continue them either! Rather link to the existing ones and
REPORT the thread for closure (or even better, and if possible, report it to merge to the already existing one). If you're not sure about what to write in the report or what to suggest, simply note that the thread is a duplicate, the mods will deal with it.
It is absolutely of no use at all to start new threads about the same subject (or even continuing duplicated ones). The only thing which will happen when you do that is that the given information will be spread out over different threads instead of being centralized in one thread and thus much information will be lost, missed, or duplicated.
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