Deleted Mail

I was looking for old mail in the Trash but could not find it. Then I noticed that the preferences deleted the trash after one week. I changed the setting to never. I looked in the Trash Bin but did not see any mail there. Is there someplace else that it is kept or is it gone for good?

Check your settings to see how the mail is removed from the server because you might be able to get it using your ISPs webmail if they have it, if you had it set not to remove mail from the server for a certain period of time