Outlook is an app that I would recommend installing via Managed Play to the device and not via an APK that you find off of a mirror site like that. Generally speaking I would recommend only distributing an app via the official channels supported by that app. If you have access to the APK directly from a developer then APK or package based install would be a supported official mechanism. If the developer is only publishing the app via Google Play then that is you're only official channel. 

Hi TORFS

Thank you for posting on SOTI Pulse!

Has the suggestions and guidance from Matt successfully addressed your query?

If not, or If you have any additional questions or need further clarification, please do let us know. We're dedicated to providing assistance and support.

Additionally, have you tried pushing the Outlook application via the Managed Google Play store to your targeted devices ? Please try assigning the application via play store and observe the behavior.

If it is a business requirement to install the application only via APK , then please do let us know that as well so that we can further investigate in that perspective.

Also, if this post has helped you in solving your inquiry, I would request you to mark the particular comment as "is solution", so others can also benefit from this information.

Warm Regards,

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