Just thought I would mention exactly what error 9000 is,
Basically it is saying that the client (your computer) has lost the ability to talk to the server (server end)
I get this when my adsl connection drops for example.
A large number of things can cause this
Most times (not all) this is due to something on the internet that is the cause, waiting for bioware to release a patch to fix the internet is a bit optimistic
You can try something like http://www.wowinterface.com/download...atencyFix.html
it may allow you to remain connected and recover