Mail Routing Issue ‘451 5.7.3 Cannot achieve Exchange Server authentication’
KB ID 0000791 Problem While putting in a New Exchange 2010 server today, I test moved a mailbox to this new site, and could not get mail to flow to the Exchange 2010 server at the clients main site. 451 4.4.0 Primary target IP address responded with: “451 5.7.3 Cannot achieve Exchange Server authentication.” Attempted failover to alternate host , but that did not succeed. Either there are no alternative hosts, or delivery...