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I have an oddity of problem with my Outlook's stability. It seems to be freezing up, not at random intervals, but based on a seemingly strange combination of configurations. I have been trying many different combinations, I've even devolved to "Cargo-cult" debugging, since I have no clue what is causing this...

Here is my set up - since I don't know for sure which settings are causing the lockup, I'll probably mention irrelevant things:

  • (relatively) clean install of Windows 8 (on hyper-v, if that matters)
  • Clean install of Outlook 2013, fully updated
  • 3 accounts configured:
    1. Hotmail account
      • configured with ActiveSync
    2. Gmail account
      • Large-ish account (several GB)
      • connected with IMAP
      • Only a few folders are subscribed in IMAP
      • Outlook is set to only display subscribed folders
      • configured to keep messages permanently
    3. Google Apps account, connected with IMAP
      • Small account
      • connected with IMAP
      • All folders IMAP subscribed
      • Outlook is set to only display subscribed folders
      • configured to keep messages permanently
  • Several Send/Receive Groups configured, to try different configurations of enabling/disable/partial the different accounts - with different send times, from 60 minutes down to 5 minutes.

The problem is that at certain points Outlook completely freezes up and I have to kill it. This is not consistent - there are some things that cause it immediately almost consistently, there are some times that it just happens by itself after some period of time (sometimes a few moments, sometimes a few hours; sometimes while using it, sometimes after I've been away from it for a few hours).

I have searched all over, and there seem to be many with similar (apparently) problem, and found numerous "solutions" (some even more cargocultish than mine), but so far none of them worked.

  • I've removed all the accounts, both all together and one at a time, and re-configured them - eventually it freezes up.
  • I've tried uninstalling Outlook, cleaning it up completely - removing files, app settings, registry keys, etc - then reinstalling - eventually it freezes up.
  • I've only enabled the Hotmail account, disabling (but not removing) the Google accounts - apparently this does not lock up.
  • I've enabled the Hotmail and the Gmail accounts, leaving the Apps one disabled - it seems like it does not lock up.
  • With all accounts enabled, it locks up almost immediately after doing a send/receive.
  • With only the Apps account enabled, it seems to not lock up.
  • With the Hotmail and the Apps accounts enabled (Gmail disabled), it seems like it locks up after a random amount of time.
  • With Hotmail enabled, and Gmail and Apps both enabled but set to receive only custom folder downloading (not all subscribed folders) - sometimes it locks up right after a send/receive, sometimes it goes for hours without locking up, and sometimes it only locks up when I send an email.
  • I've tried switching the ports for the Google accounts (SSL/465 vs TLS/587), though I have no idea if this should affect, but no real difference.

In short, I honestly have no idea what is actually causing Outlook to lock up, I might be completely barking up the wrong tree. At this point I don't really know what else to try, I'm flipping switches at random here.

I would like to have all 3 accounts enabled, ideally in several groups (e.g. pull down only important folders in a group with short interval, and all other folders in a longer interval) - obviously without freezing up at all.

I've tried putting in all the important details, if there is anything else important to add please let me know.

Another issue that occurred to me might also be connected - the Google accounts don't always synchronize properly, even after a send/receive or "update folder". At least not consistently... though I haven't been able to find a significant connection between this and that.

share|improve this question
I would highly recommend to get a better idea of what exactly is causing Outlook to lock up. You've already done some work in this regard, awesome! You should try to run Wireshark or similar utilities to see if a certain part of the client-server communication causes Outlook to wait for a reply indefinitely. You should also try running Process Monitor to capture a log of the application actions. Start the log, get Outlook to lock up and then see what the last things were that Outlook performed. – Oliver Salzburg Aug 23 '13 at 17:12

This worked for me:

  1. define IMAP accounts
  2. finish syncing them - this means not only updating the Inbox but waiting until all libraries sync and Outlook can search them (indexing)
  3. then, and only then, define ActiveSync accounts (e.g. Hotmail, Live, Outlook, etc.)
share|improve this answer

Try to break your big accounts into smaller files. Mail on Outlook used to be stored on a big file. Indexing and compressing can take a lot of time. Also, it seems you might have connectivity problems. This would certainly cause Outlook to be unresponsive.

Try search Event Viewer for connectivity problems around the time Outlook hangs. (I'm thinking downloading a large chunk via http and getting a small packet loss might drive Outlook crazy)

Check the size of the folders on disk versus the compress, indexing and auto-clean-up properties.

share|improve this answer
Thanks, but I've ruled out the connectivity issues (there were in the past but I cleaned those up). Also it is not the size of the account in question here, Outlook does fine with the GB-large Gmail account, but locks up on the barely-MB-sized GoogleApps account. – AviD Aug 25 '13 at 7:09
Try to install windbg (from microsoft windows sdk), run it as administrator, attach to outlook process, when it hangs run on windbg attached process console "!analyze -v" or "!analyze -v -hang" to have more information on who the faulting thread was and what it was doing. As found in:… – Sandokas Aug 27 '13 at 17:58

I had the same problem with Outlook 2013. I solved it by disabling hardware acceleration.

In Outlook 2013, go to File, Options, Advanced and select Disable Hardware Graphics Acceleration, near the bottom of the dialog.

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I found that EVGA percision X was creating these problems for me. when i removed it, they went away.

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I had also irregular freezes, created new accounts from scratch, started outlook in safe mode , diasbled ALL add-ins, disabled hardware acceleration , ran scanpst countless times on all pst's. really spended / lost an entire day on this and then eventually it dawned me that it had to do with internet communication, hence proxy settings ... after clearing the pac files and removing prox settings ( including reg files ) finally i can type an e-mail again in one go, or go from one e-mail account to another, or simply browse my e-mail ... without having to wait 20 - 30 - 40 seconds freezes.

I hope this can save someone else numerous hours trying the same steps one by one.

PS: this was outlook 2013, but it surely is valid for other outlook versions. A wireshark or other sniftool is not bad idea and probably would have saved me a day..

cheers, Snowride

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up vote 0 down vote accepted

I am not 100% sure what actually fixed the problems I was having, but apparently something I did made it stop happening...

After everything else I did as in the question, I did one more thing before trying to debug the process or communications - I deleted the OST file, for the problematic (small) Apps account (while Outlook was closed, of course).

Since then I have not seen the recurring problem again, so it seems apparently that this fixed it.
It may have been a corrupt file, although I did remove the account before, so...
Anyway, all the other suggestions were good, it just wasn't the issue here.

share|improve this answer

For me, my freezing problems are solely from ActiveSync / Exchange. Whenever I attempt to send an email, viewer an email, access my contacts and Outlook "Stops responding" I take a look at the Outlook icon and sure enough Outlook has connectivity options with my Exchange server. This disconnection problem occurs at any time from changing networks to resuming from sleep to starting a VPN - anytime I change my network configurations or IP addresses.

I doubt that the issue is with the Google Apps accounts (I use Google Apps and Exchange). IMAP does not require an active connection, while Exchange does. (IMAP can and Google supports it, but Outlook does not) I think the problem lies with the Hotmail Activesync setup (Mobile Exchange). Your observation "With only the Apps account enabled, it seems to not lock up." would seem to support this conclusion - simply, whenever Hotmail looses the connection to Exchange, Outlook may freeze while it attempts to reconnect.

I recommend using Hotmail in IMAP mode and see if your issues are still present.

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Outlook kept hanging up / freezing / not responding when I sent an email. I Even after a clean system refresh, online repair of office 2016, uninstall and reinstall of office 2016, only using an email account with only 100 megabits of data, deleting profile and resetting it 3 times, uncheck graphics hardware acceleration, and everything else I could find on the web, I finally fixed the problem on my Windows 10 machine.

I uninstalled Office 64bit and installed Office 2016 32bit. No problems since then.

Suprised that it was so difficult to make work on Outlook.

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I fixed mine by disabling Kaspersky's spam add on in Outlook 2016. This was on Windows 10.

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Welcome to superuser. Answers that are through are most helpful. Perhaps you could include how to disable Kaspersky's spam add on in Outlook 2016. – Bort Mar 10 at 23:05

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