It's not that you don't have a [Gmail]/Trash folder on the server. It's that Gmail doesn't have folders to begin with, only labels, and it presents to the mail client the labels corresponding to standard IMAP folders (but not other labels) as if they were subfolders of a folder called [Gmail]. So you have this folder in Thunderbird because Gmail tells Thunderbird this folder exists on the IMAP server, even though it doesn't really exist as such in Gmail itself.

Now, this being a Trash folder that's causing you trouble, I'd suggest to just get rid of it and let Thunderbird recreate it again. Go to your profile folder in the filesystem, quit Thunderbird, then go to the ImapMail/[account folder]/[Gmail].sbd folder and remove the files Trash and Trash.msf from there.

Thanks David ... unfortunately the error still pops up. I deleted the Trash. Gmail/Junk and Junk folders and I still get the error when Thunderbird starts.

Really? Thunderbird keeps wanting and failing to compact a folder it created anew? Does that folder have messages? Does Thunderbird show in that folder the same messages that you may see with webmail?

I don't know what's going on. but this being an IMAP account, you could try deleting the account in Thunderbird (both info and data) and set it up again. Quit Thunderbird and make a backup copy of your profile folder first, just in case, but everything stored on the server should be back when Thunderbird synchronises with the server after setting up the account again.

Do you have an antivirus installed? If you do, try to disable it and see whether that makes a difference. I would expect other folders to have this problem if that was the cause, but maybe there is something in Trash that the antivirus finds suspicious and is interfering with Thunderbird ability to make changes to that folder in the filesystem…

1. I am running AVG free for anti-virus. 2. I will remove the imap account and then add it back and see what happens. 3. It appears in this screen grab that I have multiple profile folders ... which one should I back up?

The profile folder to backup would be the same you had to find in order to try deleting the Trash folder within it:

https://support.mozilla.org/kb/profiles-where-thunderbird-stores-user-data

BUT…

The folder hierarchy that appears in that screenshot is a total mess, and you should consider trying to fix that before proceeding any further because, unless you created that mess yourself, it could be an indication of some filesystem corruption that could be at the root of the Thunderbird problem we're trying to fix here.

Unfortunately, I cannot help you with that because I'm not a Windows user and cannot give you proper advice on what to do about that, so I suggest you start a new thread posting that very same screenshot and asking for advice on how to fix that mess before proceeding any further. The less your computer writes to the filesystem if there is some kind of corruption going on there, the better. Something you may do while you wait for answers to your post is run some disk utility you may have to diagnose possible filesystem corruption issues.

I am not surprised that the file system is a "mess". I have been a TBird/FFox user since "forever" and the profiles have migrated from ME to Vista to XP to W7 to W10 to W11 and a lot of trash has been drug along with the migrations. Maybe someday MS will stop putting out new OS as frequently as they have in the past (I know ... its wishful thinking). I will run the disk utility as recommended. Thanks for jumping in on my query. -- John Knoxville, TN

David .. I deleted the account and then added it back .. that account now seems to be working correctly. However, in two other accounts I am now getting the same error. For one of them I was able to delete the folder but for the other one the folder [Drafts] shows as being empty. I tried repairing it with no luck and I am unable to delete it. Any additional suggestions will be appreciated. -- John

What do you mean you cannot delete it? How are you trying to delete it? In Thunderbird or by deleting the corresponding mbox file in the filesystem like we tried to do with that Trash at first?

But anyway, this problem spreading to other folders, even empty ones if I've understood it correctly, isn't normal and doesn't look like it's related to the folders themselves… Can the antivirus you're using be configured to make sure it's not interfering with Thunderbird?