When using Outlook IOS or Android app. can't send new mail. Will receive & reply fine. MS Exchange.

Hi @Mukamba, Kelvin,

Welcome to the Microsoft Q&A platform!

Based on your description, you are getting the error message EasSendFailedPermanentException when sending emails from the Outlook app on your mobile device. This error indicates a problem with the Exchange ActiveSync (EAS) protocol.

You can try a few steps to fix this:

1. Make sure the User Principal Name (UPN) matches the user's primary SMTP address. You can check this with the following PowerShell command:

Get-Mailbox <username> | fl UserPrincipalName,PrimarySmtpAddress

If they don't match, update the UPN to match the primary SMTP address.

2. Make sure the ActiveSync mailbox policy is configured correctly. Sometimes setting the refresh interval to unlimited can help:

Set-ActiveSyncMailboxPolicy -Identity <PolicyName> -RefreshInterval Unlimited

3. Delete and re-add the email account on your mobile device. This can help reset any sync issues.
4. Make sure the Outlook app on both iOS and Android devices is updated to the latest version.
5. Make sure your Exchange server settings are configured correctly and there are no connectivity issues.

Please feel free to contact me for any updates. And if this helps, don't forget to mark it as an answer.

Best,

Jake Zhang