Outlook continually downloading the same emails

[Chrissirhc]

I've had this problem before;

I have three accounts with the same mail provider.

I use pop 3 for all of them.

One of them continually downloads the same messages when I've already downloaded them before.

In the past this was because the box "leave messages on server" was not consistent on each email account.

This time it is consistent, but one of the accounts still download or 'pop' messages that have already been downloaded.

One solution is to disable leave messages on server on all the accounts. I don't want to do this as I also use the accounts for web mail.

What other possible solutions are there?