This started yesterday for me. Looking closely at the headers I saw that the duplicates were coming from another email account that I have. Looking through all my settings I eventually logged onto mobleme directly and ***; somehow I had forwarding to that email address turned on!
I had done this myself years ago for a business trip but of course had turned it off when no longer needed. Somehow it got turned on again....
Hope this helps.
Currently Being ModeratedDec 3, 2010 10:54 PM (in response to String Bass)I have a mobileme account, IMAP
I do not have Time Machine running (that was a possible cause for some)
I get duplicates of all my messages. They come a few minutes apart.
This has been happening for a few weeks now.
As far as I can tell there is no solution for this as yet, and I'm subscribing to this list so that I might find out as soon as there is one.macbook/macmini, Mac OS X (10.6.5)
Currently Being ModeratedDec 16, 2010 2:55 PM (in response to String Bass)*Solved as of now*
I called apple because I had the same issues that everyone had with their mail and after almost an hour later with no luck the person that was helping me told me an option I could use. Therefore I deleted my account and reinstated it. Unfortuantly when using POP once you delete your account on your mac book all of your message become erased but I was able to save all the ones I wanted to save.
Here is what I did:
1) Highlight the messages or inboxes that you want to save.(If you want to save anything you need to highlight it otherwise it will get erased when you erase your account)
2) Once highlighted go to mailbox and click on archive mailbox.
3) Once opened click where you want your saved messages to be stored so you can restore them later.
4) Then I had to open up preferences through the mail on mac.
5) I went to accounts and highlighted the source of where my mail was coming from and clicked on the minus key on the bottom. This will delete your account.
6) Then close mail and reopen it.
7) Go back to preferences and press the addition key follow the steps to recreating your account on mac mail.
8) Once created now go to file and import the mailboxes that you saved in the previous steps.
9) It should then show up under on my mac and you can copy and paste your messages back to the original inbox or leave them there ( your choice).
As of right now I have no longer had problems. This was my last resort to solve the problem. If the problem consists Apple suggests that you call the help center from where your mail originates from such as mine is from yahoo. Hope this helps! =]MacBook Pro, Mac OS X (10.6.5)
Currently Being ModeratedJan 3, 2011 9:23 PM (in response to missvegas91)Not a solution for me, I'm afraid. As I said, mine is an IMAP account (Mobile me). The duplicates come and go: some days there are no duplicates, other days, all my incoming messages are duplicated. I receive one first, and then a few minutes later along comes the other one.macbook/macmini, Mac OS X (10.6.5)
Currently Being ModeratedFeb 5, 2011 2:22 PM (in response to Ernie Stamper)Hi Ernie,
We're new to the Apple Discussions. We recently experienced this duplicate email retrieval problem for which we've read the string of messages. We followed the instructions in deleting the MessageUIDAlreadyDownloaded 3, closing mail then rebooting. Despite doing that we still have that problem. We have a PowerBookG4 with Leopard (10.5.8) and Mail 3.6--and have had this computer for 6+ years. After the computer crashed yesterday, suddenly this duplicate mail problem appeared. Each time we've deleted the messageuidalreadydownloaded3 file, close mail, and reboot, upon opening mail it again tries to retrieve previously read messages. We do access mail from 2 different mac (the other is an iMac24 with snow leopard)--the other computer is not experiencing this problem.
Besides deleting that file, you mentioned forcing mail to "freshen" that file. How do we do that? Will that make a difference?
ThanksPowerBookG4, Mac OS X (10.5.8), Mail 3.6
Currently Being ModeratedFeb 5, 2011 11:26 PM (in response to philipjb)For all of our POP accounts, we were able to fix this duplicate mail problem as instructed by Ernie Stamper. Essentially, you need to delete the MessageUIDsAlreadyDownloaded3 file in the path: User>Library>Mail>MailUIDsAlreadyDownloaded3, and empty your trash. Then, go through your Mail so that all of the message have been read (nothing should show a "blue dot" which indicates it's an unread messsage). Once you do that for each of your POP Mail accounts, close and re-open mail, and let it synch/bring in all the messages (duplicates). When Mail is done synching all of your POP mail boxes, then click on the "circle" icon for your first POP Mail box so that all of these "unread" = "blue dot/circles" messages sort to the top of the list. Those are the duplicate messages, that can be deleted. If you do this for each of your POP mail boxes, you will be able delete all of the duplicates. When Mail re-synchs, it should no longer bring in duplicates.PowerBookG4, Mac OS X (10.5.8)
I am having the same problem as TimK. I have 1 IMAP account coming in to MacMail, 10.6, no rhyme or reason to when or why suddenly emails appear in multiples - sometimes 2 copies, sometimes 12. Usually happens with a handful of emails that have already downloaded, in the previous few hours. Hoping for a fix!
Currently Being ModeratedSep 17, 2011 12:42 PM (in response to String Bass)
after receiving duplicate copies of many messages in several different [non-gmail] pop accounts, i still encountered the same problem.
i tried the various solutions contained in several forums, but the only one that solved the problem was on this string:
Those having this problem, please use the Finder to open Home/Library/Mail and locate the file named MessageUidsAlreadyDownloaded3. Use Get Info to see when this file was last updated -- should be after the last time new messages were downloaded?
THANK YOU, ERNIE STAMPER!! problem solved.
Currently Being ModeratedAug 22, 2013 11:57 AM (in response to diana292)
The User Library has been hidden in Lion and Mt. Lion. Quit Mail first. Then Open your User Library (Home Folder) in the Finder, click to open the Go menu, hold down the Option key, and Library will then appear in the list for you to open.
Once that is open, click to open the Mail folder, then the V2 folder and finally the MailData folder. In that folder you will find 3 files named to include MessageUidsAlreadyDownloaded3. I think you will need to remove all 3 of those from Mail Data. Once you have done that (maybe save them on the Desktop for now), Relaunch Mail and was described earlier should apply.