In ups.com,
Chuck typed:
How do I use a POP 3 account in Microsoft Outlook to have the choice
of choosing my sending addess. I am running on an Exchange server
and we have two domains that we send through. I am trying to find a
way to allow the user to choose which domain address will appear on
the from box when he sends his email. I do not want to pay for the
software that allows this and was wondering if this was possible
through a POP 3 account.

I have tried almost everything I can, please help....

Using POP and Exchange in the same profile can work, but I don't recommend
it. I'd much rather have everything handled by my central mail server, for
myriad reasons. However, if you do have both accounts in the same profile,
you can use the Accounts button in a new message to choose the sending
account..

But again, really, I'd suggest you rethink this entirely. You'd be better
off setting up the user with two Exchange mailboxes and showing him how to
use the From field....or, set up the other address(es) as mail enabled
groups with his 'main' mailbox as a member, and grant him Send As rights.
www.ivasoft.biz has fairly inexpensive add-ins that can make this easier,
but they aren't really needed.