Probably, since the 'allmail' folder contains allmail.

My problem is that for the past year or more contents of various of my folders have turned up empty. I frequently move posts from my inbox to my folders. These same emails are automatically posted in "All Mail." This means two of the same emails/duplicates exist in various folders. I am wanting to know FOR CERTAIN if the reason my folders are turning up empty of various emails I had stored there is because I deleted the duplicate email from "All Mail"

Yes, that is the cause. In Gmail, there is only one real folder: Allmail. Thunderbird imitates it by duplicating all other folders. You will save roughly half your disk space, and half your internet transfer time, and much cpu resource use by unsubscribing from allmail.

Thank you so much for that information! Would you be so kind as to tell me how I can unsubscribe from all mail? Thank you!

- highlight the account in folder pane - rightclick and select 'subscribe' - untick the box for Allmail - close and restart thunderbird

NOTE: the disk space may still be there, even though not used. if interested, you can do this after the restart: - click help>troubleshootinginformation - scroll to 'profile folder' and click 'open folder' - exit thunderbird - click the imapmail folder - click the <IMAP account folder' - if you see allmail and/or allmai.msf, just delete them - restart thunderbird </p>

Thank you David for taking the time to help me. I just unsubscribed from All Mail. Had no idea I could do that!