Smart Forward on iOS devices, or "Why am I seeing so many calendar invites?"

Over the last several days, our Outlook and Exchange support teams have noted an increase in the number of cases opened where customers are seeing a calendar invite sent over and over again, even with no interaction on their devices.  Usually we will send our support article to our customers, but there have been questions over how would we see it inside our own environment.

In some cases, this is what we will see in our Outlook Inbox:


Then, for the actual meeting, we will see something similar to below:


One of the questions we get is why is this happening?  What can be done to stop it?

We have been able to work with Apple and determine is that all of these users all happen to have an iOS device, which was recently updated.   From what we can tell, the location field is what is triggering the issue.  We would have the time to leave and location field will somehow trigger this and then send a SmartForward.  When this happens, all recipients will then get a 'copy' of the updated meeting.

What if I suspect I have this issue?

There is a way to tell if you have this issue!  The first step would be for you to create a ticket with Premier Support via the Premier Support Portal!  If you do not have a Premier Service contract, you can also open up a case with our Professional Support Incident team.  We will require the following data:

  1. Calendar Diagnostic Logs from the "Get-CalendarDiagnosticLog" cmdlet.  This data will need to be from the meeting originator (in our example above, from Tony G.) and the Send on behalf user.  (In our example above, we would need it from Lee S.)
  2. We may also need Active Sync Mailbox logging, however you need to check with your Support Professional first.

Within these logs, your support professional will look for specific calls from the affected devices and if we see the SmartForward triggered in a certain way.  Please understand we have to be fairly vague about how this call is made, and your support professional may not be able to give you additional details.

Update as of 6/30/17:

We have been able to work with Apple and can confirm there is a fix in progress on the Apple side.  However, we do not have an ETA on release, only that it will be in a future release.  Per our discussion with Apple, I've added in some additional workarounds.

Update as of 7/20/17:

Apple has released iOS 10.3.3, which should contain the fix.  Please update to iOS 10.3.3 and check to see if the issue is resolved.

Update as of 7/28/17

Apple has confirmed iOS 10.3.3 does include a fix for the SmartForward issue.  Please note that ALL iOS and watchOS devices MUST be updated to prevent additional occurrences.  Apple has published the release notes at and for the iOS and watchOS issues.  While we are still seeing some trailing reports of meetings invites, this issue is different than the SmartForward attendees issue.

As such, I'm going to remove the workarounds and instead replace it with the fixes:


  1. Use Outlook for iOS.
  2. Remove the location of the meeting.
  3. Disable the "Time to Leave" feature via the "Settings > Calendar > Default Alert times" commands
  4. Update to iOS 10.3.3 beta or iOS 11 beta.
  5. You can also contact Apple, as they may have additional workarounds.


To correct the SmartFoward issue, please upgrade to iOS 10.3.3 and watchOS 3.2.3.