Mavericks and Outlook - repeated download of same emails

I had the same problem as the OP. Email was getting duplicated (or worse) in Outlook 2011 which started with the installation of OS X Mavericks. I checked all settings in Outlook and could find nothing wrong. Rebuilt the database in Outlook -- didn't help. Ran lots of system and disk utilitiy programs -- no dice.

Then, I started remembering that I'd had a similar problem when I started using iCloud. We were getting duplicates of contacts, events, email, etc. So, I headed to the the "Internet Accounts" control panel. Sure enough, there was a checkmark for "Mail" in the iCloud account. I unchecked it. There was also a checkmark for "Mail" in my POP account; I left that one alone.

(I don't know whether I had that iCloud "Mail" checked before the installation of Mavericks or not. I wonder whether the Mavericks installation turned it on, similar to how the IOS updates keep turning Bluethooth back on...)

I made this change over four hours ago, and - so far - I have not had any duplicate (or worse) email whatsoever in Outlook. They were coming in non-stop. So, for me, this seems to have fixed my problem. If things go haywire once again, I will post here and say so.

I'm guessing Mavericks uses iCloud to synchronize accounts in some fashion. Once again, I wish iCloud was more like Dropbox. Somehow the logic of the iCloud sync seems non-logical to me.

Hello,

I have duplicate emails in Outlook since Mavericks install. Exiting the sleep mode (or exiting the screensaver) I found many time-out errors and Outlook re-downloaded every mails stored on the server.

I found a solution:

1 - Display information of "Microsoft Outlook.app" (located into the folder Applications/Microsoft Office 2011/Microsoft Outlook.app. (Select the Microsoft Outlook.app "file" into the Finder and press Command+I)

2 - Check the box Disable/Prevent App Nap (On my french version "Empêcher App Nap")

Because I am not sure that Office 2011 manages App Nap, I disabled App Nap also for Word, Excel and PowerPoint.

I hope this workaround will work for you as well as it works for me!

Thanks Terry. I have unchecked iCloud mail and we'll see if this stops the torrent of duplicate email. I can tell you that merely deleting emails on the server (or not storing them for even one day) did not solve the problem. Nor did reinstalling Mavericks. So, I hope you are right that iCloud mail is functioning like a server and downloading each time I boot up Outlook 2011.

alas, Terry and Jake, I attempted your workaround and still the duplicates come in torrents

One factoid I wonder if anyone can deduce a problem from: whenever I hit "advanced" on the outlook account setup, Outlook hangs--even when I've created an entirely new identity. Why would selecting advanced create that issue? Is it a corrupt pref file? (I'm way out of my depth here)

thanks for your idea...until either Apple or Microsoft offer a workaround it seems we're stuck

I said I'd come back and post if I started having multiple email messages again. Well, I do. Everything went fine for over 24 hours, but now I am getting them again, so my "fix" is no fix at all. Back to square one.

I see Outlook is also logging error messages as others have reported. These are "inactivity timeout" with an error code of -16999 and "Connection to the server failed or was dropped" with a different error code for each instance.

I've taken poster JoFr123's advice and checked "prevent app nap" for Outlook. We'll see how that works out. I'll post my results for good or ill.

After following earlier poster JoFr123's advice, I had checked "prevent app nap" in the Get Info box for Outlook. It's now been over 24 hours and I have yet to receive duplicate (or multiple) email. Further, I have not received any of the error warnings regarding failed connections, etc., since making the change. So far, so good. Have others had luck with this tactic?

If I find that this fix holds, I'll be back and post my results. Likewise if the issues start reappearing.

I have the same problem but I do not understand your fix. I cannot find the file Microsoft Outlook.App and cannot find the app nap check box. Please could you be more specific. I'd really like to try it. Sorry if I'm being stupid

JuleUK - Yes, the language is a bit confusing. Let me try to simplify this, as this is a very easy fix.

Open the Application folder. This is the folder that contains all your applications such as Safari, Mail, TextEdit, etc. Within that folder, you will see another folder named "Microsoft Office 2011." Open that. You will now see the various applications which make up Office 2011, and you will see Outlook there.

Click once on the Outlook icon to select it. Now, while holding the Command key down, press "i" (i as in info). When you do this, a tall narrow window will open named "Microsoft Outlook Info." In the top section of that window is a section named "General." You will see a little box you can check named "Prevent App Nap." Click in that box to indeed prevent app nap. Close all the windows. I always restart after something like this, but I doubt you have to.

That's what we're doing.

I'm still having sucess with this fix ...going on two days now, and no multiple or duplicate email or error messages regarding server timeouts, etc. Fingers are still crossed here.

Thank you Terry for this explanation. English is not my mother tongue, that is why it was a little bit confusing.

Have a nice day.

You're doing fine, JoFr123. There are people here from all over the world. We like it that way!

Is the "check Prevent App Nap" fix still working for you? It's looking good here, so far.

Yes, it is still working for me since 1 week. No time-out error and no duplicated mails. This workaround seems to be working on the mac book pro of my wife too.

Sorry to report that the Outlook 2011 prevent nap app option is not working for me. Thousands if duplicate emails still pouring in.

Sorry to hear that you're stil getting duplicate email, jakeworld. For me, the "check Prevent App Nap" fix is working. Since I checked that box, I have not had a single issue.

I'm guessing that there's more than one way you can be getting duplicate email. Is Outlook generating multiple connection error and server time-out messages for you, also? It seems that the "check Prevent App Nap" fix has to do with that issue as well as the duplicate email. Perhaps, if you are not getting the error messages your issue is not quite the same, though the symptoms are similar.

I'd still be very suspicious of something to do with iCloud, jakeworld.

Thanks Terry. No, I am not getting any server time-out or other error messages -- just reams of duplicate email. Also, as someone else suggested, I unchecked iCloud mail (as well as Apple mail) in internet accounts, and so other mail sources/servers don't seem the source of the problem. Somehow, the opening of Outlook seems to be rerregistering my account with Outlook in some way. Then again, I quit the program everytime it starts pouring in new emails and so maybe I need to let all of the duplicate email come in and then hope that it stops after the email dump.

jakeworld, I believe those of us with duplicates whose problems were solved by checking the "Prevent App Nap" box all had accompaning connection error messages. As you are not receiving those, it seems to me that your problem is indeed different than ours.

I'll be interested in what solves your issue, but - short of an iCloud issue - I have no idea at the moment. Do check the Microsoft discussion areas also. They will have plenty of good ideas there.