Solution found. 1) Under account settings, Copies and Folders, Draft and Templates, make sure that the first option is checked (keep drafts in the "Drafts" folder of the account name (as apposed to the "Other" option), as explained in more detail in other entries 2) close and re-start Thunderbird 3) install the FolderFlags add-on 4) right-click on the folder that started behaving as draft folder, and under Properties, go to the Flags tab. I found that for both "problem" folders the "draft" box in the list of folder flags was checked. Uncheck the draft flag. 5) close and re-start Thunderbird 6) the folder(s) will no longer behave as drafts and the messages they contain will no longer show "This is a draft message". The folders will re-appear in their correct alphabetical order under the Local Folder list (previously they had a "draft" symbol and were appearing right at the top of the Local Folders tree, together with the other standard folders such as Trash, for example.

Comment: the solution outlined above worked for me. No guarantee that it will work in every similar situation. However, it is still not explained what made Thunderbird change the properties of these two folders into draft folders. This is a bug that should be corrected.

Further comment: Thunderbird continues to randomly "pick" local archive folders and transform them into "draft" folders. This has happened at least once since I posted the solution above and involved a completely different folder. The problem could be fixed by simply unchecking the "draft" box in the folder flag list. However, this is a bug that needs to be fixed.

Update: I have reverted this entry to the status of solution not found yet, as the problem continues to occur again and again: Thunderbird randomly changes the status of local archive folders to "draft" folder, with the result that all messages contained in that folder become "draft" messages, and the folder icon type also changes. One has to manually undo this by unchecking the "draft" flag in the folder properties as described above.

Dear Thunderbird developers, this is a bug that needs to be corrected! Thank you.

Hi You mention you are using an add-on with Thunderbird, and from your description it sounds as if the 'flag' setting causing the problem is actually in the add-on, not in Thunderbird itself. Is that correct? If so, check the current version of the add-on is compatible with the version of TB you are running. Add-ons are developed separately and do not always get updated to work with the current TB version. Each add-on has a page where you can find version compatibility, comments from others using it who may have similar problems, and a means to contact the developer.

Hi Agnes,

Thank you very much for your reply.

Please note that I installed the FolderFlags add-on because Thunderbird had transformed two local folders into draft-type folders and thus every message contained in those folders became "draft" messages, even those I had received from another person. I have been using the add-on to be able to see the flag list under Properties and then uncheck the "draft" flag, after which the folder returns to its original, non-draft status. Again, the problem appeared before I had ever installed the add-on.

As I wrote, the problem continues to occur, although not all the time. Every now and then a local folder gets changed to "draft" status again. This seems to happen predominantly with folders where I file copies of sent messages more often (i.e., folders that are "used" more often.

Thank you for clarifying that. Can you say which email provider you use, and whether POP or IMAP? There is a setting in TB that directs which folder is considered the Drafts folder, and sometimes the online email server and TB settings clash over where Drafts should be stored (Gmail in particular). Check in Account Settings, click on Copies & Folders. You should see Drafts and Templates, and under that, a Keep draft messages in: option. Make sure it is sending Drafts to the correct folder.

Thanks for this reply as well.

My account is of the POP type. The provider is part of the T-Mobile system in Europe.

Regarding the TB setting -- I had checked this already. Please see the entry from 6th November, first point. I just re-checked it and it is as it should be.

I have used TB "forever" (= as long as I can remember, certainly longer than 15 years) and never had this problem before. This would suggest that the (suspected) "bug) was introduced with a relatively recent version update.

When searching TB Help for tips how to deal with this issue I noted that a few other users have reported similar problems, although not necessarily very recently. One such entry, for example, is "Thunderbird Local Folder behaves like Drafts".

Other users recently reported similar issues but in their case simply correcting 'Keep draft messages in:' fixed the issue. Try changing that setting to another folder, close and open TB, then change it back. Beyond that is ... delete a session or settings file and have TB rebuild it, which is beyond my expertise.

I also have this problem. I am a longtime user of Thunderbird. Over the last couple of months, two different standard long-time subfolders in my main mail account (on the server, not local storage) have suddenly been reclassified by Thunderbird as DRAFTS folders, and all the messages within them have been reclassified as Draft Messages. If I click the X beside "This is a draft message" on each of those saved old messages within these transformed folders, the individual draft "designation" disappears until I click away from the message and come back to it. I can't reclassify the subfolder, and I can't reclassify the messages. They both continue to imagine themselves as DRAFTS folders and DRAFT MESSAGES. I wish it were more clear to me how I can, oh, do a right-click to reclassify the subfolder from a DRAFTS folder back to being a SUBFOLDER, and to also correct the classification of all the messages within these randomly reclassified folders back to being saved messages instead of drafts. Mine is an IMAP account.

I've been battling this problem for several months now. I use an IMAP server hosted by ionos.com. At random intervals with no reason apparent to me, Thunderbird reclassifies a folder with messages as a Drafts folder with the consequences mentioned in other posts. My Settings entry for Drafts is pointing to the correct Drafts folder which is not the one that got magically reclassified. Without installing the third-party add-on mentioned in previous posts, I have to go through contortions to straighten things out. This includes using the web interface to access my mail, creating a new folder, and moving all of the messages from the reclassified folder into the new folder. In the web interface, everything looks and works fine. Only Thunderbird is doing strange things. Even though I have been a Thunderbird user for longer than I can remember, this tries my patience enough for me to consider moving onto another mail client.

It would be appreciated, if everyone suffering from this issue, could provide some info to questions. Your answers to the following may help pin down what is causing that folder flag to get set incorrectly.

Q1: For those with Pop accounts - is the pop account set up as a deferred account using 'Global Inbox Local Folders' account OR using own account folders?

OR does this question not apply to you?

Q2: If POP using ' 'Global Inbox Local Folders' account regarding Account Settings > Copies & Folders entry for Drafts. Which option are you using 'Drafts folder on' OR 'Other' ? (and then choose 'Drafts on Local Folders')

OR does this question not apply to you?

Q3: If pop using own folders or IMAP regarding Account Settings > Copies & Folders entry for Drafts. Which option are you using 'Drafts folder on' OR 'Other' ? (and then choose 'Drafts on imap account name')

Please let us know if you are pop or imap.

Q4: Do you use something other than 'View' > 'Folders' > 'All' on a A)regular or B)periodic basis or C)never? eg: 'Favourite folders' or 'Unified' view etc ?

Q5: Do you use 'Offline' mode on a A)regular or B)periodic basis or C)never?

Q6: Addons - please list all addons you have installed stating whether they are enabled or disabled. Note: you can quickly locate this in Thunderbird : 'Help' > 'More Troubleshooting Information' scroll down to 'Add-ons' section. Copy all text and paste into the reply.

Q7: When this problem occurs what did you do immediately prior to noticing change: examples: started TB in offline mode and it occurred when I went to online mode ? Started TB and swapped to View> Folders > Unified or vis versa ?

Thanks for helping.

This happens to my Thunderbird too, starting relatively recently -- and creeping along, infecting what appear to be random folders.

1: For those with Pop accounts - is the pop account set up as a deferred account using 'Global Inbox Local Folders' account OR using own account folders?

OR does this question not apply to you?

A1: I have multiple POP accounts defined in Thunderbird, each with a set of folders. I don't use Global Inbox Local Folders.

Q2: If POP using ' 'Global Inbox Local Folders' account regarding Account Settings > Copies & Folders entry for Drafts. Which option are you using 'Drafts folder on' OR 'Other' ? (and then choose 'Drafts on Local Folders')

OR does this question not apply to you?

A2: Doesn't apply.

Q3: If pop using own folders or IMAP regarding Account Settings > Copies & Folders entry for Drafts. Which option are you using 'Drafts folder on' OR 'Other' ? (and then choose 'Drafts on imap account name')

Please let us know if you are pop or imap.

A3: POP accounts, Drafts folders default to one per account.

Q4: Do you use something other than 'View' > 'Folders' > 'All' on a A)regular or B)periodic basis or C)never? eg: 'Favourite folders' or 'Unified' view etc ?

A4: Never.

Q5: Do you use 'Offline' mode on a A)regular or B)periodic basis or C)never?

A5: Never.

Q6: Addons - please list all addons you have installed stating whether they are enabled or disabled. Note: you can quickly locate this in Thunderbird : 'Help' > 'More Troubleshooting Information' scroll down to 'Add-ons' section. Copy all text and paste into the reply.

A6: Attachment Extractor, Compact Headers, Limit non-BCC recipients, Manually sort folders, Xpunge. None of these are recently installed but the problem is relatively recent. I have a record of every Thunderbird version upgrade installed if that would be useful.

Interestingly, I'd never used Manually sort folders. I was able to use it to move folders flagged as drafts where they belonged, instead of bunched together at top of higher-level folder containing them. That's progress, but they're still incorrectly flagged as draft folders.

Q7: When this problem occurs what did you do immediately prior to noticing change: examples: started TB in offline mode and it occurred when I went to online mode ? Started TB and swapped to View> Folders > Unified or vis versa ?

A7: Nothing unusual or noteworthy -- just reading/sending email. And I may not immediately notice a newly infected folder -- so I can't connect an infection with an action.

I believe the effected folders have got a folder flag for drafts.

Please use this addon:

• https://addons.thunderbird.net/en-us/thunderbird/addon/folderflags/

How to install addon:

• https://support.mozilla.org/en-US/kb/installing-addon-thunderbird

If you download the xpi file - image below is a guide.

Once addon extension is installed and is visible in 'Menu app icon > Addons and Themes' > Extensions: In Folder Pane:

• Right click on effected folder and select 'Properties'
• Select the 'Flags' tab
• uncheck any flag that has been set, let me know what flags were set.
• click on OK