Thunderbird downloads duplicate email on my iMAC and not other new emails
When I open up Thunderbird on my iMAC it keeps downloading the same duplicate message and doesn't download the remaining unread emails that are on the server. I have the ability to see these new emails on my iPhone which doesn't use Thunderbird so the issue appears to be with Thunderbird. I am on release 102.11.1 & the iMAC is on 11.7.6.
Opaite Mbohovái (1)
This sounds like a log jam. Are you using a pop account ? If yes, then access the webmail account via a browser I'm presuming you can see all the new mail in the webmail Inbox. Delete the email which keeps downloading or move to another server folder. Empty the server Spam and Trash folders.
Back in Thunderbird, click on 'Get Messages'.