Thunderbird has lost all my folders

Hello Elaine. 
Thank you for contacting AVG Support Community. 
We're sorry to hear that you're facing this trouble. 
We will certainly check and help you.
Please confirm us how you suspect that this issue is caused by AVG programs. 
Also please confirm us how long you are facing this issue. 
If possible, please provide us the screenshot which shows no folders found in Thunderbird. 
In case you need help with creating a screenshot, please refer to the below article.
http://support.avg.com/SupportArticleView?l=en&urlname=Create-screenshot
Thank you and keep us updated. 

I've lost all my folders on Thunderbird

Hello Elaine. 
Thank you for contacting AVG Support Community. 
We're sorry to hear that you're facing this trouble. 
We will certainly check and help you.
Please confirm us how you suspect that this issue is caused by AVG programs. 
Also please confirm us how long you are facing this issue. 
If possible, please provide us the screenshot which shows no folders found in Thunderbird. 
In case you need help with creating a screenshot, please refer to the below article.
http://support.avg.com/SupportArticleView?l=en&urlname=Create-screenshot
Thank you and keep us updated.