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If a user runs the Outlook App on multiple devices of the same OS, then Outlook App will provide the same device ID for the user on those devices. This will weaken the enforcement of MFA that is based on the device ID.
3 - Outlook app can change the device ID sporadically on the same device
Occasionally, the Outlook app may change the device ID of the same device. As a result, applications that use the device ID will stop working.
For organizations that have a problem with any of the concerns above, you can block the Outlook App from accessing your Exchange mailboxes. Microsoft provides a guide below:
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