Thunderbird is locking up on a message and I have to delete it on Bellsouth otherwise it will download the same email over and over. How do I fix?

Question

It started a couple of weeks ago. I noticed one email being downloaded several times. After checking a lot of things I deleted the e-mail on Bellsouth and Thunderbird then downloaded all of my e-mails. Over time it has started to do this several times in one batch of e-mails. The downloading bar will say it's down loading 1 (or whatever the number is) of say 71 messages. It may download 1 or more then it stops downloading. I go into Bellsouth and delete the last message downloaded and hit Get Mail in Thunderbird to start the process over.
If I don't delete the last e-mail downloaded when I hit Get Mail Thunderbird will download the same e-mail again and stop. Some times it will start a download and work for an extended time and then stop the download without downloading a single e-mail.

Answer 1

That sounds like an anti virus choking on a mail. Norton is fond of doing this, but it is not alone.
Restart the operating system in '''[http://en.wikipedia.org/wiki/Safe_mode safe mode with Networking]'''. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: [http://windows.microsoft.com/en-us/windows-8/windows-startup-settings-including-safe-mode Windows 8], [http://windows.microsoft.com/en-us/windows/start-computer-safe-mode#start-computer-safe-mode=windows-7 Windows 7], [http://windows.microsoft.com/en-us/windows/start-computer-safe-mode#start-computer-safe-mode=windows-vista Windows Vista], [http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/boot_failsafe.mspx?mfr=true" Windows XP], [http://support.apple.com/kb/ht1564 OSX]
If your mail download in this safe mode then look to your anti virus and disable email scanning.