In this post, let’s have a look at the error message “5.7.705
5.7.708 – 5.7.705 Access denied, tenant has exceeded threshold, 5.7.708 Access denied, traffic not accepted from this IP” that you get when working with Microsoft 365 Exchange Online.
These are the errors that you usually receive when there is a problem in delivering the email message that was sent by you. These errors are generated and sent by Office 365. This is usually alled as DSN which stands for delivery status notification or in simple words bounce messages.
NDR or Non-delivery report is one of the common type of message that you receive which indicates to the user that the email was not delivered.
5.7.708 – 5.7.705 Access denied, tenant has exceeded threshold, 5.7.708 Access denied, traffic not accepted from this IP
The majority of traffic from this tenant has been detected as suspicious and has resulted in a ban on sending ability for the tenant.
Ensure that any compromises or open relays have been resolved, and then contact support through your regular channel.
For more information, see Fix email delivery issues for error codes 5.7.700 through 5.7.750 in Exchange Online.