Office 365 Organizations: Think Twice Before You Upgrade to iOS 11

by | Sep 20, 2017 | Collaboration | 0 comments

Update: On Tuesday, September 26th Apple released an update that corrects this issue – iOS 11.0.1. If you are experiencing this problem, simply update your device to restore compatibility. You can find more details on Apple’s support page.

Yesterday, September 19th, Apple introduced the latest version of their mobile operating system – iOS 11. As expected, the update brings new entertainment, security, and personal productivity features to Apple phones and tablets (you can read more about it here). Unexpectedly, the new version of iOS – which users can download now – features a major incompatibility with one of the most common email platforms. As users discovered yesterday, the native mail app in iOS 11 is incompatible with Office 365,, and Exchange 2016 in Windows Server 2016. We expect this to cause some support headaches for a lot of customers, so here’s a quick guide on the issue and how you can work around it.

The Issue

As I mentioned above, this issue impacts users of the native mail application with email in Office 365,, and Exchange 2016 on Windows Server 2016. Specifically, users will be unable to send or reply to email using the native mail application. Microsoft and Apple are working together the resolve the issue in a future update, but there is no timeline for correcting this.

What Can You Do?

Organizations that are impacted by this have a few options to consider. Many businesses will likely want to execute a couple of these options.

  • Notify your users of the problem and ask them not to upgrade to iOS 11. If you have a Mobile Device Management solution that allows for management of Apple updates, you should hold off on iOS 11 until this issue has been resolved.
  • Move users to a different mail app. This problem impacts the native mail app, Microsoft recommends that users download the Outlook for iOS app. If you have a Mobile Device Management solution that can push applications, you can do this for your users (we wrote about Microsoft Intune’s application management capabilities here).
  • Organizations that are using Exchange Server 2016 have the option of disabling HTTP/2 in Windows Server 2016. The links at the end of this blog post will have more detail on that.

We believe that this issue will impact a lot of companies. Hopefully, the workarounds above can help to mitigate the user backlash. Microsoft and Apple will be working together to correct the issue. You can learn more about the issues and track updates on their respective knowledge base articles:

If you have questions, need assistance resolving this issue, or are interested in implementing an MDM solution that can better manage these types of problems; reach out to us at or 630.832.0075. We’re ready to help.