Reinstall Thunderbird - How do I save Emails (not Gmail)?
Two problems: 1) Inbox messages Read, but later pop back as Unread. 2) Sent messages appear twice in the Sent Folder.
How do I save (Export?) my existing Inbox & Sent emails? The suggestion using Gmail will not work for me, I use that account for other purposes.
I would like to try Uninstalling Thunderbird, Re-Installing the program and Importing the data back. How?
Opaite Mbohovái (1)
Lets start at the beginning.
Uninstalling and reinstalling almost never solves anything.
Your item two indicates your using Live or Gmail as duplicate sent messages are normal for both providers without manual intervention. Perhaps you could confirm which and if your using IMAP mail (I think you are, hence the duplicates)
Your Item 1 is probably related, most likely however in the timing of mail checking. anything less the 10 - 15 minutes is usually an issue with Gmail. Live just drop your connection attempt.
Please post (Copy to clipboard and paste here) the account settings shown in Troubleshooting Information on the help menu.