At least 70% of the time I open Mail, one or more messages suddenly duplicate themselves. Both can be opened, but only one can be deleted. The one that remains is empty.
The only solution I have found is to quit Mail and then re-open it. Subsequent messages work normally.
Does anyone have similar problems?
I’ve seen that occasionally. It doesn’t really seem to hurt anything. I assume it is some sort of server confusion and it figures itself out eventually.
I use the Ventura version of Mail. I see similar behavior on a few of my accounts. The common thread for me is that the affected emails have been forwarded by automated filters at the email server level from one account to another. I’m also fairly sure the problem is independent of whether an account is POP3 or IMAP (can’t check at the moment).
Try rebuilding Mailboxes (macOS/Mail/Mailbox/Rebuild) in case there is some corruption.
I have seen that duplication come in the Sonora version of Apple Mail when I am getting duplicate copies of a mass mailing addressed to two of my email addresses. I can only delete one of the mails after receiving the two, but what is left is blank and goes away after a while. If you use multiple emails for different things, it’s easy to wind up receiving duplicates from different emails. If it’s bothering you, it’s easy to remove one of the email addresses from the mailing list, although the senders don’t always stop sending to that address.
Thanks, Jeff! Based on your description, I think I may have found the cause. I have two iCloud addresses. I use only one, but I think that one is somehow related to the other. Both have been enabled. I have disabled the one I don’t use. I’ll know tomorrow if it works.
Meanwhile, I took the opportunity to delete old messages – all 17,659 of them. I think I heard my iMac breathe a sigh of relief.