Is this a pop or imap mail account ?

It is IMAP

re:seems to be an issue with emails I move to saved folders reappearing a few seconds after I move them If the message reappears in original folder, then it would seem logical that a Message Filter would run on same message again, hence duplicates. So I agree with you that it could be effecting the creating of duplicates.

re:I tried compacting folders and deleting .msf files in my profile. A sensible approach. When you accessed the profile name folder, to locate and delete .msf files: Did you exit Thunderbird before deleting the .msf files?

In the Message Filter Apply filter when: Did you select 'Filter before Junk Classification' ? under 'Perform these actions' Check: Did you select 'Move message to' or 'Copy Message to'?

re:I have filters set up to move certain emails to stored folders on my hard drive Is the filtered message moved to another folder in the same imap account or to a folder in 'Local Folders' mail account?

Do you have an Anti-Virus product scanning incoming emails? If yes, what AV are you using? Suggest you test to see if AV is causing an interruption that is effecting the result. It is necessary to rule out the actions of an AV. Either: Start computer in 'Safe Mode with Networking' and then start Thunderbird. OR Access AV and stop it scanning all Thunderbird files and folders and also stop it scanning incoming & outgoing mail. Please run computer in 'Safe Mode with Networking' for a reasonable period of time in order to determine whether 'moved' emails are not actually being moved because they reappear in original folder and whether duplicates are being created.

Is this a gmail account? What server are you using? What OS are you using? What version of Thunderbird are you using?

To answer your questions: Did you exit Thunderbird before deleting the .msf files? Yes. In the Message Filter Apply filter when: Did you select 'Filter before Junk Classification' Yes. under 'Perform these actions' Check: Did you select 'Move message to: Yes. Is the filtered message moved to another folder in the same imap account or to a folder in 'Local Folders' mail account? Folder on Local directory. It is from my cable service Charter Spectrum, it is possible they have some sort of AV scanning the emails, I called them today, they claimed it is not their problem. I'll try the Safe Mode with networking. The server is the cable service, mobile.charter.net OS is 10.14, Thunderbird is 60.8.0 (64-bit)

Tried restarting my mac in Safe mode (by restarting holding down shift key) and launching Thunderbird, didn't really work, got a white window that said "Offline Settings". Not sure if this is what i was supposed to do. Sure wish I could get this resolved. More annonying than the duplicate emails with the filters is that when I manually move an email to a folder, it reappears a few seconds later so I need to delete them after I thought I moved them.

re: I called them today, they claimed it is not their problem. That's a standard response because you are not using their webmail and they appear to have limited knowledge beyond that.

re: Tried restarting my mac in Safe mode (by restarting holding down shift key) and launching Thunderbird, didn't really work, got a white window that said "Offline Settings".

On Windows OS there is a difference between starting computer in 'Safe Mode' and 'Safe mode with Networking'. 'Safe Mode' does not allow internet connectivity, so when Thunderbird starts, it cannot connect with servers and is forced to start in 'offline' mode. This sounds like what happened in your case.

You need an option that offers something like the latter 'Safe mode with Networking' to allow internet connectivity.

re:it is possible they have some sort of AV scanning the emails, They are likely to have some sort of spam filter in operation, but not Anti-Virus as that is your responsibility. Do you have any type of Anti-Virus program on your computer? Norton, McAfee, Avast, Malwarebytes etc etc ? It is probably scanning any files that get uploaded/downloaded. As you are using Imap then there is a constant upload/download going on. Stop the Anti-Virus from scanning emails or files, even if for a while long enough to determine whether the interuption caused by the AV is effecting the imap account.

TEST: What happens if you: disable one of your filters so it does not run automatically Allow download of emails as normal to Inbox. Then manually run that 'disabled' filter on the Inbox

re :Is the filtered message moved to another folder in the same imap account or to a folder in 'Local Folders' mail account? You say: Folder on Local directory.

Sorry but the answer is not entirely clear. Q: Are you moving an email from imap Inbox folder to another subscribed imap folder in the same mail account? (I think you mean this one.) OR Q: Are you moving an email from imap Inbox folder to another folder outside of the imap account in the default 'Local Folders' mail account?

To understand your current setup..........What setup are you using for downloading of emails? Q: Do you have settings to download full emails or only headers for all subscribed folders? Q: Do you have settings to download full emails for some subscribed folders and only headers for other subscribed folders?

What settings have you got selected in the Account Settings for the imap account? Q: Are you using all of the settings as shown below or do you have slightly different settings?

• Right click on imap mail account name in Folder Pane and select 'Settings'
• Select: 'Synchronisation & Storage'
• Select: 'Keep messages in all folders for this account on this computer'
• click on 'Advanced' button
• make sure all folders are visible, including any subfolders and make sure all checkboxes are selected for download. Click on OK.
• Select: 'Synchronise all messages locally regardless of age'
• Click on 'OK'

Q: Are you already using all of the above settings? If slightly different, tell me what settings you are currently using.

I'm not sure how to restart in safe mode with networking on a mac or if it is possible.

1. re:it is possible they have some sort of AV scanning the emails, They are likely to have some sort of spam filter in operation, but not Anti-Virus as that is your responsibility. - My cable company has a antivirus program I use, it is called Charter Security Suite, I tried uninstalling it, but the problem still happens, I don't have any other AV program.

2. TEST: What happens if you: disable one of your filters so it does not run automatically Allow download of emails as normal to Inbox. Then manually run that 'disabled' filter on the Inbox - I just tried this, doesn't help, the emails come back to inbox in addition to being moved to the folder.

3. re :Is the filtered message moved to another folder in the same imap account or to a folder in 'Local Folders' mail account? You say: Folder on Local directory. ....imap folder in the same mail account? (I think you mean this one.) -NO OR Q: Are you moving an email from imap Inbox folder to another folder outside of the imap account in the default 'Local Folders' mail account? -YES, Local folder, on my hard drive.

4. Q: Do you have settings to download full emails or only headers for all subscribed folders? - Not sure where that setting is?, would guess it is set to full emails. Q: Do you have settings to download full emails for some subscribed folders and only headers for other subscribed folders? - Not sure where that setting is?, would guess it is set to full emails for all folders.

5. What settings have you got selected in the Account Settings for the imap account? Q: Are you using all of the settings as shown below or do you have slightly different settings? - Everything is set as you say to except the Spam folder and Trash are not currently checked. Should they be?

My Thunderbird screenshot:

I'm wondering if I should try reinstalling Thunderbird and updating with files from my backups?

There is no point in uninstalling and reinstalling Thunderbird as this is not a problem with the program.

Please post an image showing the filter.

Here's one that has had the issue, there are a bunch set up, keep in mind the problem also happens for emails I manually move to a saved folder not using filters.

Try this: Thunderbird > Preferences > Advanced > 'General' tab click on 'Config Editor' button It will say be careful :) In top search type: expunge Look for line: mail.imap.expunge_after_delete The 'Value' may be 'False' double click on that line to toggle the value from 'False' to 'True'. close window. click on 'OK'

Restart Thunderbird. Filters should run. Report back on results regarding whether moved emails are deleted from imap folder.

Nope, sorry, they still reappear.

Usually, upon 'Move' out of an imap folder and account, the email is deleted off server, but Charter Spectrum is one of those servers that does not seem to do as expected. I have a workaround idea you can try.

Do you have 'Tags' that are recognised by the server? If yes. You could use one of those 'Tags' for a special purpose to get around the server not recognising Move setting a delete action. The idea being to Tag an email that has been filtered. The next time filter runs if it finds email with that tag, then delete.

Try this in Message Filter. Add a second rule to one of your 'Move to' filters which says: 'Perform these actions' 'Move message to X folder' 'Tag Message' and choose a Tag which is only going to be used to identify emails to delete. For demo purpose I'll call the tag 'Done'.

Then create a new filter called 'Del Tag' Message Filter. 'Tags' and 'contains' and 'name of specific tag' eg: 'Done' 'Move Message to' select the 'Trash on imap mail account.' OR you could use 'Delete Message', but if it appears in Trash then it is easier to see what is/isn't working. Put this 'Del Tag' filter above other filters in list, so it runs first.

The idea being that this 'Del Tag' filter locates all emails on server previously 'moved to Local Folders' that now have the 'Done' tag and moves them to Trash, so that subsequent filters that run should not locate email and therefore not create a duplicate.

Then exit and restart Thunderbird, so filters run automatically. Yes you will get duplicates this first time, but I'm hoping a load of emails will get 'Tagged'. Then the next time it runs, the 'Del Tag' filter should delete those tagged emails, although you could run the 'Del Tag' filter manually on Inbox.

Report back on results.