Mail, Moving messages stuck

I think the problem will be with the All Mail Folder in Gmail. It appears that you are using it from your image above. It will show in the Archive mailbox in Mail. Check your other devices and see if the Archive Mailbox is set to the Gmail All Mail also.

The All Mail will show messages in any folder it appears in. I hide this folder at the gmail site so it doesn't show in Mail. You might also check to see how deleting messages are set at the website. Gmail's default is to archive. You might want to change that also.

The images below is what I use to make gmail work best with Mail:

First, check your other devices and see if the mailboxes are set to the server mailboxes and not local. Especially the trash.

I don't think it's a gmail issue nor a connection problem either. It's a wrong setting or corrupt file that was migrated from your old computer.

Try this process below. You will need to recreate customized settings, but it should reset your Mail user preferences:

Remove Container file Mail:

Quit Mail.

In the Finder, select Go, then Go to Folder. Copy and paste the path below and hit GO:

~/Library/Containers/com.apple.mail

Move the whole com.apple.mail folder to the Trash, and open Mail and test. If all goes well, you can empty the trash. You may need to re create your user settings.

If the above doesn’t work, repeat the process with this folder:

~/Library/Containers/com.apple.MailServiceAgent

If there is a problem or you wish to restore the old file, first, Quit Mail.

Then open the Trash. Right click on the folder and choose Put Back from the menu.

If nothing works, it might just be best to delete the gmail account from internet accounts in system preferences. Restart the computer, then add the gmail account back in.

If I understand you correctly, when you delete the email on the new iMac, it does not delete from the other devices. Since you migrated your account from the old mac, it copied the cause from it.

Check to see if it isn't set up as POP on the new iMac, or the other devices might be set up as POP. That sounds like the issue.

It appears to be IMAP. Is this happening with both accounts? Or is only Gmail?

Is the problem that it doesn't sync and delete messages from the other devices? The title says problems moving messages, & the description says deleting messages.

Check Mailbox Behaviors and see if all mailboxes are set to server mailboxes and not On My Mac.

If you switch the iMac to using Wi-Fi (disconnect the Ethernet cord) does the behavior change?

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