The fact that Antivirus Norton is not compatible with Thunderbird,you must configure it manually, perform as explained below:
- Open Norton Antivirus
- Select Configure > File Systems>Auto-Protect
- Cross check the box [Exclude files/folders selected]
- Click [exclusions] and [Files/Folders]
- Select the folder [Inbox] (without extension) under:
Really good work about this website was done. Keep trying more – thanks!