Outlook Sign-in Error On iOS and Android Fixed

Microsoft has confirmed a problem signing in to Outlook from your phone. As far as is currently known, the error only occurs in Exchange environments and can be resolved using an interim solution that has now been presented.

This is reported by Bleeping Computer. Microsoft has explained the possible causes in a new support document and published a fix for the Outlook login error.

Users who have problems connecting to Exchange mailboxes from iOS or Android get the error message “User email address has been blocked on this device by your administrator”.

“The error occurs in a hybrid Exchange environment, for mailboxes in on-premises Microsoft Exchange Servers or Exchange Online,” Microsoft now writes in the newly published support document. However, the devices were not actively blocked by the responsible administrator. According to support, the likely cause is a missing Exchange ActiveSync (EAS) access rule that allows users with Outlook iOS and Android apps to connect to the Exchange Online server.

To fix these connectivity issues, admins need to ensure that Hybrid Modern Auth is enabled. A new Exchange Online access rule for Outlook mobile apps must also be added.

Help from Microsoft Support

The procedure required for this requires the following:

• Verify that you have Hybrid Modern Authentication support enabled in your organization (see this support document for more information ).
• Create an EAS device access rule in Exchange Online that allows connections from Outlook for iOS and Android.

To do this, run the following commands:

Connect-ExchangeOnlineNew-ActiveSyncDeviceAccessRule -Characteristic DeviceModel -QueryString”Outlook for iOS and Android” -AccessLevel Allow