Critical issue solved on outbound3 (Resolved) Issue / Performance
10 days

At approximately 11AM EST, one of the ExchangeDefender outbound network endpoints (outbound3.exchangedefender.com) was brought into rotation without all the relay ACLs authorized. The result is the message below for some clients/domains whose policies did not load properly. The error they received is a 500 Relaying Denied, and it's been fixed/addressed. 

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.

The following organization rejected your message: outbound3.exchangedefender.com.

If you received this error message, please go to your Sent Items and resend the message.