I would think your question really belongs in a bullgard forum. I would suggest simply owning the need for a backup and using a backup tool of your choosing to make backups of the folder you want. Relying on some piece of software to make a usable backup of your Thunderbird profile is really not something I would be comfortable with. Especially if it calls it mail backup.

The import export add-on has a scheduled profile backup option. Perhaps you could use that.

https://addons.thunderbird.net/en-US/thunderbird/addon/importexporttools/

Hi Matt, thanks for your comments/link. I have contacted Bullguard support several times and they have escalated the issue though no solution as yet. Reinstalling Bullguard, as they suggested, did not solve the problem. Initially they said it may be an issue with the latest version of Thunderbird so I chose to post on this forum because I could not find a way of contacting Mozilla. However, I have since discovered that my file backup profile also copies files from my C:\User folder which includes all emails so I have been duplicating somewhat. Best wishes for Christmas and the New Year.

Why would you contact Mozilla? They no longer develop Thunderbird and have not done so for the past 4 or 5 years.

I didn't know that! I have been using Thunderbird for about 2 years without any issues so never needed any support. Time to abandon it and move on I think.

It is still developed. Just not by Mozilla. But feel free to use any email client you wish.