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Hi there,

We are currently moved to Office365 Cloud email services, but just for a few distribution groups, I am constantly get the following errors:

Delivery has failed to these recipients or groups:

<email distribution group> 

The email address you entered couldn't be found. Please check the recipient's email address and try to resend the message. If the problem continues, please contact your helpdesk.

When I did the message trace, it shows:

However, if I sent the email to it inside Office365 Outlook WebAPP portal, it was delivered successfully.

Please help.

Thanks,

Kevin