If it keeps downloading same files, it sounds like the popstate.dat file has gone awol. The 'popstate.dat' file keeps a record of what has been downloaded. You need to access the Profile folder and delete this file. The Profile folder is a hidden file, so you have to make hidden files and folders visible to see it. make hidden files visible: * http://kb.mozillazine.org/Show_hidden_files_and_folders Profile folder extra info: * http://kb.mozillazine.org/Profile_folder_-_Thunderbird In Thunderbird * Help > Troubleshooting Information * click on 'Show Folder' button * a new window opens showing your Profile folder * '''Close Thunderbird now''' * click on 'Mail' folder * click on the 'mail account name' * scroll down and locate 'popstate.dat' a DAT File. * Delete 'popstate.dat' * close the window - top right X * Open Thunderbird Thunderbird will create a new 'popstate.dat' file and start to download everything that is in the server Inbox to the thunderbird mail account Inbox. But only the once. After fixing the popstate file you may have loads of duplicate email messages. You can use this Addon to help remove them: * https://addons.mozilla.org/en-US/thunderbird/addon/remove-duplicate-messages/ remember to compact folders on a regular basis.

It worked ,thank you!!