Outlook Data File / Double Email

I keep an Outlook data file on my external HDD that I carry between work and home. How do I get it to stop downloading emails twice!?

I have three accounts; a Gmail account (which doesn't have this problem), a work account that uses SmarterMail and another account that's set up through Windows Live Mail.

You should have some settings to allow you to remove the message from the server when it is downloaded.

If that doesn't help, maybe there is some sync setting you might use.

Work-wise and study-wise I have to leave those messages on the server and I can't *find* any settings to keep track of when messages were downloaded. I was hoping Outlook 2010 had the ability to notice from the client side...