Mail in mailbox disappeared

[Jeremy06]

I can't see any of the mail in one of my Mail mailboxes, but when I go into Time Machine, I can see all the mail in that mailbox in the Today (now) view. How can I get it back? Thanks.

 

[McGiord]

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What type of email you have POP or IMAP?

 

[Jeremy06]

It's an IMAP Microsoft Exchange Server account.
I had a problem with iCal on this account, so I had deleted that calendar, and when I re-entered the same iCal account, I left checked the associated mail and contacts accounts. I ended up then with 2 of the same Mail accounts and the original one (with everything from the past in it) I can't see anymore.
Thanks.