5.7.700-749 Access denied, tenant has exceeded threshold
August 5, 2018•448 words
tl;dr if you're getting this error, it's an automated threshold that Microsoft Support has to reset or expire over time
check your message trace logs for signs of abuse and go ahead and call support
I'm currently working on an ~800 user hybrid Exchange deployment and due to some issues with the existing 2010 environment decided to deploy an Exchange 2016 server to handle hybrid duties. Becauuse the customer is switching from Mimecast inbound/outbound to EOP/ATP I decided to route all messages ...
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