We are running Exchange 2010. Last night we upgraded the router firmware. Reboot both Exchange mail server and router. After that, some users receive Undeliverable message with this error: “Your message wasn't delivered due to a permission or security issue. It may have been rejected by a moderator, the address may only accept e-mail from certain senders, or another restriction may be preventing delivery”. Only a few users receive this message. DNS lookup and MX record look good. What could be the problem?
Bob Lin, MVP, MCSE & CNE Networking, Internet, Routing, VPN Troubleshooting on
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