I'm using Outlook for Mac 2011 14.4.2 with latest updates installed on OS X 10.9.2. For several days now I have been unable to access email in Outlook. Everytime I open outlook and check mail it says 'determining changes' and cycles through inbox, trash, sent, drafts etc. It spends ages doing this but ultimately no mail is received at all. Settings include options for downloading message headers and when to sync and update folders. To access these settings, click Outlook Preferences Accounts, select the IMAP account, and then click Advanced. For information about the primary IMAP account settings, see Basic IMAP account settings for Outlook for Mac.

TL;DR

Objects in an Exchange Online mailbox unable to be synchronized to the Mac Outlook 2016 client cause significant CPU usage and impact battery life.

The Symptoms

The recent Spectre & Meltdown updates have me keeping a closer eye on CPU usage and slowdowns in general. In doing so I have been reminded just how much CPU Microsoft Outlook 2016 for Mac takes up. On both my Mac systems it’s continually on the top apps list taking up 70%+ of a core. Way more than it should. I get plenty of email, but really not enough to keep it so busy. On my laptop it’s impacting battery life significantly whenever Outlook is open. This morning I decided to dig a little deeper into what’s going on.

Alongside the CPU usage, I noticed consistent network activity from the Outlook app as well - between 100-200Kbps. When I’m mobile and using a MiFi or tethering to a phone, that adds up. There must be something behind that. My setup is pretty simple - a corporate email account run through Exchange Online / Office 365, and both Windows and Mac Outlook clients. The Windows Outlook 2016 app is well behaved, using minimal resources. This must just be a Mac problem.

Investigating Outlook

Outlook 2016 for Mac doesn’t give you much detail on what it’s up to, but it does have a few things we can look at.

First up - Sync Errors (Available from the Window menu). Nope, nothing there.

Next - Sync Status. This looks interesting - It’s constantly trying to sync a particular folder. That item pops up again and again.

But why? To get more info we need to head back to the Sync Errors window. Sync Errors has a settings icon at the top right coder, that will let us “Turn on logging for troubleshooting.” That’s a well hidden configuration setting. It doesn’t bother to mention that you need to restart Outlook for the logs to actually show up.

The process of enabling logging for Outlook on Mac is detailed at this Microsoft page

If I open up the directory “~/Library/Containers/com.microsoft.outlook/Data/Library/Logs/” now I have a log file to look into. A log file that is filled with messages like this:

From the timestamps, Outlook for Mac is nonstop trying to sync with Exchange Online but getting errors and then instantly trying again. This is very poor design, not backing off or throttling when an error is encountered or ignoring the offending object and moving on with the sync operation.

Here’s the critical part of the log errors: “The recurrence format wasn’t valid., The duration between startTime and endTime (6.00:30:00) of the recurrence is greater than the minimum duration between two occurrences (1.00:00:00).”

The error message itself narrows down a little bit what we’re looking for - a meeting invite for a recurring meeting.

Finding and Removing the Problematic Objects

To find these items, I needed to switch back over to the Windows Outlook client, because obviously these items weren’t syncing down to my Mac properly. I opened up the offending “2011” folder, and arranged the messages by Type. This way we can get straight to the Meeting Invites. Outlook does show you “Type: Recurring Meeting” in the messages list so this makes it easier.

I have all of these old emails saved in a PST folder, so it was easy to delete a few and see if anything changed on the Outlook for Mac side. Eventually I found this innocent looking meeting invite which was causing all my problems (there were actually two nearly identical ones with different lists of people on the “to” line which is why Outlook for Mac was failing to sync 2 objects not 1).

To me it looks like a perfectly fine meeting - not one that would generate an error message about the duration or recurrence. Nevertheless, without that mail in the folder, Outlook for Mac was able to continue syncing, and once completely synchronized the CPU usage calmed right down, now idling at 0.0-0.1%.

Unfortunately the Outlook for Mac client can get into these situations without behaving correctly (backing off and not hammering Exchange Online with requests), or alerting the user to a persistent sync problem. Most people who have this issue have likely never looked into that Sync Status window at all. It was such a frustration that I decided to put a nice serene waterfall image at the top of this page just to relax me when proofreading it or for others that have to go through the painstaking procedure of finding and deleting un-syncable objects. Hope it helped.

Last update: February 2020
Applicable to: Outlook 365, 2019, 2016, 2013; Windows and macOS

Here’s a question we got from a reader about her Microsoft Outlook client not showing new incoming emails automatically:

Unlike my when using my Google Mail account, it looks that my Microsoft Outlook 365 folders are not automatically updated with incoming email messages. It seems to me that any new email items are updated probably once in 15-20 minutes. I know that i can update Outlook by hitting F9 or use the Send/Receive All command. My question to you is how can i possibly set Outlook to automatically update its Inbox folder more often, if possible as often as Gmail does. If that’s not possible, can you explain how often mail check happens and how to refresh Outlook so that new inbox emails are shown as fast as possible?

If you ever used Microsoft Office Outlook as your PC e-mail client, you might have noticed some delay in your inbox refresh rate. Typically, it takes your incoming mail a bit more time to arrive when compared to web email services such as Yahoo Mail, GMail and Outlook.com. Those typically auto update your inbox folder entries whenever new email hits your mailbox.

In today’s tutorial, i will show you how to make your Outlook inbox update automatically in shorter intervals so that the latest incoming messages are shown once they hit your server.

Outlook inbox auto-update on Windows

• Open Outlook, and hit the Send/Receive button.
• Click on Send/Receive Groups drop down box and Select Define Send/Receive Groups.

• Under All Accounts, Click on Schedule an Automatic Send/Receive every.
• Change the Minutes value from 30to a smaller number. Note that setting this value to less than 5 min might lead to duplicated entries in your inbox.

• After changing Close the Dialog box.
• Now your Outlook inbox will automatically refresh every 10 minutes.

Increasing the refresh rate of all your Inboxes

• In the Send/Receive Groups dialog (steps to open it explained beforehand), go to “Setting for group All Accounts“
• And then set the Schedule an automatic. value to the required refresh rate. Again – beware the fact that too frequent updates could lead to duplicated Outlook email entries; which are generally time consuming to fix.

Auto-updating the Outlook calendar

To ensure your Outlook calendar is always up to date, proceed as following:

My hope though is for a way to trigger the eraser while in Presentation mode. There is currently no shortcut for this, and trying to click on the bottom-left menu to grab the eraser is near impossible on a Smartboard. Erasing lines one at a time: Click the Pen button and choose Eraser. You can also right-click and choose Pointer Options→Eraser. The Eraser appears. Using the Eraser, click the line you want to erase. Press Esc when you’re finished using the Eraser. Erasing all the lines on a slide: Press E or click the Pen button and choose Erase All Ink on Slide. Is there an eraser in powerpoint for mac.

• In the Send/Receive Groups dialog, hit the Edit button.
• Then in the left hand side, ensure that your email account is marked.
• Then under Folder Options ensure that your Calendar folder is marked.
• Hit Apply.

Auto-update you Outlook global address / contact lists

• Same as in the section above, just ensure that the Contacts folder is marked for auto sync.

Note: You can always trigger an update of your email folder by hitting F9.

Refresh email on Mac

If you are using Outlook on macOS to read your Gmail, Hotmail or Exchange email, you can shorten your Outlook folders synchronization interval, so that auto update processes will be enabled and launched more often.

Kindly proceed as following:

1. Open Outlook for MAC
2. In the left bar, you’ll note your GMail, Hotmail / Outlook.com or Exchange Account.
3. Make a right click and select Account Settings.

4. The Accounts dialog will appear, at the bottom right of the screen hit the Advanced button.
5. Open the Server tab and set your sync interval accordingly as shown below – Note that for IMAP accounts (GMail and Outlook.com) the minimum value is 2 minutes.

Note: for slower connections like cellular hot spots, you might want to consider to check the Download message headers only box.

6. Hit OK.
7. Close the Accounts dialog.
8. You are all set 🙂

Additional Reader questions

Refresh Outlook manually

Couple of readers asked how to manually trigger an update of their mailboxes.

On Windows:

Update all Outlook folders:

This procedure will trigger a Send/Receive action on all Online and offline accounts (could be exchange, Hotmail/Outlook.com, Yahoo, GMail) that are setup in your Outlook.

Side Note: that you might as well define specific Accounts/Folders group and trigger an update on those specifically. For example – refresh only your private GMail account and not work Exchange during weekends.

1. Open the Send/Receive tab.
2. Hit the Send/Receive All folders button (or simply hit F9).

Update a specific folder:

1. Open the Send/Receive tab.
2. Hit the Update Folder button.

On macOS:

Refresh your entire mailbox:

• Enter the Home tab.
• Hit the Send & Receive button.

Update specific folder:

• Open the Organize tab.
• Hit the Sync Folder button.

Use VBA to refresh your mailbox

The method SyncObjects can be used in order to sync one or more Send/Receive groups for a specific user. In case you are interested in building a macro to automate your auto syncs, feel free to ping me via the contact page.