Outlook 2011 for Mac keeps corrupting

Posted on 2014-07-18
Last Modified: 2015-02-27
I have a client running Outlook 2011 for Mac OS X Mavericks.

The account is set up as POP.  There's a lot of email, about 26GB in total (lots of attachments).

Every couple of days, one of the following happens:

1. The Outlook splash screen appears for about 1 to 2 seconds, then closes; nothing else shows up.
2. Outlook states that the identity has to be rebuilt. The rebuild takes 2 seconds, and nothing is there afterwords.
3. Outlook starts normally but the account is completely empty.

Scenario 1 is the most common.

Using the database utility, I locate the main identity (usually just a few MB in size).  I click through the various (several) backed up identities and find the one that is >26 GB, and I right click it and set it as main identity.  I then rebuild this (takes around 45 mins to an hour), and it runs fine.  It properly downloads the emails missing since the last backup of the identity, and we're good to go.

Then a couple of days later it all happens again.

Lots of free space on the drive (couple of hundred free GB)

Any chance I've hit a practical maximum for database size? Outlook isn't reporting that it has an issue with it.  In fact, I think another user there has over 60GB of email.

Anyone experienced this?

Question by:DaveWWW
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LVL 53

Expert Comment

ID: 40204389
May be disk dorectory corruption. Open disk utility and run Verify Disk. While you are at it run Repair Permissions.

Author Comment

ID: 40212209
I ran verify and repair, restarted the machine and ran them again.  After restart and run, I got green success messages.  None of the repairs appeared to have anything to do with Office/Outlook specifically, but Outlook has been running so far for about a day.  If it runs for a couple of more days, I think I'd call it fixed.

Author Comment

ID: 40631777
It looks like the problem actually was that Outlook for Mac requires a significant amount of free disk space in order to work properly.  It appears that problems arise when the amount of free space on the disk is less than the size of the email folder. Not positive, but that's when I notice problems.
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Author Comment

ID: 40631852
I've requested that this question be closed as follows:

Accepted answer: 0 points for DaveWWW's comment #a40631777

for the following reason:

Could not find any other reason than free space.
LVL 53

Accepted Solution

strung earned 500 total points
ID: 40631844
Generally speaking, Macs need 15% free space on the drive.
LVL 29

Expert Comment

ID: 40632047
That's somewhat incorrect.  15% of 500 GB = 75 GB.  15 % of 1TB = 150 GB.  If you need to use disk space for storage, you're just wasting it by keeping it unused.  That 15% figure may have been true over a decade ago, but you don't need that much anymore.

You generally need just enough free Disk to cover your SWAP (Virtual Memory) usage.

As long as you leave an amount free disk that's equivalent to your RAM or 4 GB, whichever is greater, you shouldn't run into problems.  RAM isn't going to be always 15% of free disk.

Author Comment

ID: 40632751
I know that in the numerous times I've had to repair a large Outlook for Mac database, it was unsuccessful unless the free disk space was at least 3 times the size of the email folder.
LVL 29

Expert Comment

ID: 40634183
That's specific to Outlook during repair and seems seriously broken.  It's not needed during normal usage.  I don't use outlook, but I do run numerous other software and never had trouble with my smaller free disk space allocation.  I suspect it's caused by broken permissions or disk errors that you fixed with Disk Utility, or bad programming by Microsoft and not any real disk space usage needs.

If you need to repair mail that frequently, then you should look into alternatives.  Mac Outlook is outdated and I've seen too many people struggling with repairing mail.
Mac Office 2011 is really Windows Office 2007, featurewise, with hooks to recognize Windows Office 2010 file formats.

The reason to use Outlook is for the combination of Mail, Calendar and Contact organization when connecting to Exchange.  It might be easier to use Mac Mail, Mac Calendar, and Mac Contacts.  You connect to exchange using IMAP, CalDAV, and CardDAV, respectively, and get all the same basic features.  There's less mail folder rebuilding.  I usually migrate users on Mac away from Outlook because of that.

Outlook freezes too frequently on Macs and even on Windows.  There's just too much feature creep in it.  Repair is used far too often, a sign that they didn't make it robust in the first place.

I only responded after you've accepted strung's answer, because you've selected something that didn't actually solve your problem, since your initial question said,

Lots of free space on the drive (couple of hundred free GB)
I've never needed anything close to 15% free disk in any OS, unless it's a file server and I'm migrating/transfering files between systems and doing backups.  Normal office drone software never needs anything close to that.

You can monitor your disk usage during the rebuild.
To monitor Disk usage, you can open up finder and do Shift Command c to show your computer
Selet your Macintosh HD and Press Command i to open up the Info.

You can also open a terminal and periodically run df -h to display your free space.

Author Comment

ID: 40635167
Thanks very much serialband. The Outlook file in question is approx. 70Gb and it looks like the problem occurs when a backup of the Outlook profile takes place, eventually eating up most free disk space.  I have several clients using Outlook for Mac and this is the only one who has such a huge email database.

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