How to make thunderbird download only new mail from Gmail

[webgenius]

I installed Mozilla Thunderbird today. I checked the option "Automatically download new messages". Still Thunderbird downloads all the mails, which I have already seen in my Gmail inbox. How can I make Thunderbird download only new mail and not delete any mails from server?

[mod-the-pc]

Go to Tools>Account Settings and enable Leave messages on server to ensure that the mails are not deleted from the server

[webgenius]

How to make it download only new messages?

[prasad_den]

Originally Posted by webgenius

How to make it download only new messages?

In GMail options, go to POP settings, and enable POP forwarding from now on.. Do it again even if you have already enabled it.. Then any message that you receive from now on only will be forwarded to your thundrbird..!!