I don't think I can help but what is the file size of the Trash Folder that won't compact? (triple dots beside 'new message' and 'Show Folder Size' which is a toggle). Are you using the routine compaction setting or trying to do it manually?

Compacting is seemingly done automatically (weird because I usually must do manually). I checked the "size" c/o Properties of the trash folder but the size given is the size of the content (like 0 if empty or 450 k for small trash), not the "folder size" as such.

So, would you give me the size of the Trash Folder in question, please?

As said, you can't see the "size". only the size of the content. So, is 0 or 500 kb or anything, depending on what is in the trash. Note that the warning comes without asking to compact, while trash is working OK and ... can be compacted manually. So a warning it seems without any reason. Earlier it was only in the IMAP email, now starts in one of the POP emails.

I don't understand your answer. When you choose to see the Folder sizes, what is the size beside the trash folder that you are having trouble with? And how many items are in there? See attachment

I already explained. The size shown is the size of the items in the trash folders. As the trash actually works despite the "alarm", the trash can be empty (0 kb) or with like 3 small items 500 kb. See as example, in one of the affected emails: 17 items in trash 769 Kb. After emptying trash and compacting successfully (yes!) folder 0 items 0 kb. At the same time the (false) alarm comes... while everything is fine... Must be some software bug

you should not be compacting the trash really, just empty it periodically using the menu entry and the file holding trash will be deleted and a new one created.

The trash can be compacted either directly or from the header of the email (then all folders are compacted). The trash folder cannot be deleted. In my case deleted mails go to the trash, the trash can be emptied and compacted. Despite the "warning"

you should not be compacting the trash really, just empty it periodically using the menu entry and the file holding trash will be deleted and a new one created.

The Trash Folder is cumulative in its size, even though it can be emptied - and compaction does return the value to zero when no emails are present. I haven't yet reached the file size for automatic compaction to take place but manual compaction does remove the 'blank space'. Removing the emails does not zero the content size.

The only way round the questioner's problem, I see, is to delete the data file in the profile belonging to the relevant trash folder (which I did in the early days before I understood compaction) with success.

I can't, however, give the questioner a set of instructions as I need the trash file size so I can make sure he deletes the correct file, based on size, as it may be that he doesn't have his file extensions visible.

Further to my earlier details, as said the error seems to come without a good reason as everything works, see here the two trash folders of the emails that produce the alert as shown. I did do "repair folder" but that does not help. The locations are totally different for the folder. I have another email that has a similar address for the folder as in trahproperties1, but there no alert yet. I am not sure I can delete that find - if I can locate it...

Further to my earlier details, as said the error seems to come without a good reason as everything works, see here the two trash folders of the emails that produce the alert as shown. I did do "repair folder" but that does not help. The locations are totally different for the folder. I have another email that has a similar address for the folder as in trahproperties1, but there no alert yet. I am not sure I can delete that find - if I can locate it...

As I said above, let me have the folder sizes and I should be able to help. However, don't put anything into the folders once you've let me have the volumes as I'll need to write out a solution.

I am sorry but I don't understand. As said earlier: - I can delete emails that go to the trash without any problem - the "size" of the trash is the size of emails in it - I can delete the trash that as shown earlier is size 0 kb and no files.

See the screenshots I provided earlier. As said it seems the warning seems to be a false warning as everything works fine.

The size indicated by the TB display of the Trash Folder is unlikely to be the cumulative size of the email contents if you have deleted any files from the Trash since the last compacting of the databases.

I think I will leave it here and move on.

If I am to give you instructions to have TB generate a new Trash Folder, I also need to know the present size so I can see what problems there are in your profile folders. That info needs to be fed back so I can think about whether there is a different problem.

I don't understand why you are unwilling to let me have the TB display giving the size of the Trash Folder but I won't proceed without it.

As said.... All 0.

In my first reply, I gave you instructions on how to determine the file sizes. Your screenshots are not what I asked you to tell me. Although the file sizes should be the same, I'd be grateful if you could send me the figures that I asked for.

Again, trash before deleting content. "Folder Properties" of the Trash gives exactly the same information. After doing "delete trash", all 0

So, while I am getting the instructions sorted DO NOT add anything to the Trash folder. NOTHING. I also must warn you that you must follow the instructions I send you completely and not do something different. Read them first and, if you're happy and confident, go ahead. Don't invent stuff to do that I haven't said to do.

I cannot help you with the IMAP account. I would assume that it behaves in much the same way as the POP email set up but I don't have experience of the locations of files so you will have to get info from someone else.

I am assuming that, because this is a trash folder, you are happy to lose ALL the emails contained inside. If there are any emails (like, one or two - not all of them) you want to keep that are in the Trash folder, move them NOW.

This ONLY works with the Trash folder on a POP account. Please do not try this on any other file or folder. I have done this on my own OS running W11 and Thunderbird version 128.5.2esr (64 bit).

I am assuming that the data files in the Trash folder have corrupted which is why I'm suggesting you do the following. If they haven't corrupted and there is a different problem then this won't resolve it. At the very least, you should have eliminated one possibility.

1. Close Thunderbird

2. Close all open programs

3. Make a folder on your desktop and call it what you will

4. Navigate to the folder named mail.beijing1980.com along the path that's specified in the image you posted (re-attached here). On a Windows computer it would probably be located on the C:\ Drive so starts C:\Users if you're running a Windows OS. Not sure if you're using a MAC as you said 'MAS' in your original post - but I'm guessing that you are. You would need to follow the path and navigate to that folder.

5. Inside this folder you will have two 'Trash' data files. The .msf file should be fairly small but the other should be around 234KB, the folder size that you told me it was. If it is substantially different, let me know for my info cos it would be good to know that a displayed size was not close to being the same as the data file.

6. Before we do anything, look at all the file sizes of the other items here. I want you to check that there is nothing overly big (a size in Gb) just in case the reason that no 'disk space' is being offered has to do with another of the files here. Let me know if there is anything overly large. But we can proceed even if there is something.

7. Move both 'Trash' files to the folder that you created on the Desktop.

8. Launch Thunderbird. Thunderbird will now realise that it's lost the Trash folder and make you a new one. This is what it does on Windows and I have no reason to see why it shouldn't do this on a MAC.

9. Look in the window you still have open and two files with the same name starting 'Trash' will have been made. Their file sizes will be minimal.

10. Check the file size in Thunderbird of the new Trash folder and it should have a zero value (or, better, it won't display any size at all - and it will have no emails inside it).

11. You should keep the folder on your desktop for a while in case you have any problems and wish to restore the old Trash data files (at the loss of the new ones) but I've done this myself and have not found there to be any.

The IMAP account is different as TB is only mirroring what's on the Server. I would start by closing TB and then emptying the trash on the server. Then locate the Trash data files on your HD. However, I'm not at all competent with doing this and I'm not sure what the effect would be - I would assume that Thunderbird would just recreate new Trash data files - so you need to ask further advice before proceeding with the IMAP account.

I have posted the notes about 30 minutes ago but they're not showing. If they can't be seen by you, please let me know and I'll repost them.

OK, sure. I will read first and if confident strictly follow instructions