If you removed your account (from AD, I am guessing) and you still have the issue, it would be interesting to see what happens to other users of this 3rd party app. BTW your account isn't a domain admin is it (or one of the other priviledged accounts...)? I know you will say your account hasn't changed, only the BB, but I have to ask....
As it's the weekend, I wonder if you happened to do this while some updates were applied to Exchange and/or BES (again sounds like a long shot but stranger things have happened)
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