How do I set my default email address? It seems to flip flop around to a few different emails depending on how my blackberry feels that day. It's really annoying as I want my default email address to be just one and I really want to set it that way. Any way of making it one address perminatley?

Main Menu - Options - Advanced - Default Services - select your default

^^Exactly. EXCEPT: If you have Email1 set as default, but your last email to John Doe was from Email2, the BB will default to using Email2 for ONLY that contact until you change the default in an email to that person.

Does that make sense... that would explain why you have seen some variation in the "Sent Using".

Got it, thanks! Now to fix my stupid calendar!

Ah, yes. I had my calendar items all under the wrong email... I had to make sure ALL was correct in Outlook, first. Then completely delete the BB calendar data and restore.
How to Clear/Delete all your Address/Calendar items at once - BlackBerryFAQ

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