SOLVED: 4.2.1 Unable to connect.” Attempted failover to alternate host…
If you see the following error in your Exchange 2003, 2007, or 2010 queue, there are three things you should do to troubleshoot the problem: 451 4.4.0 Primary target IP address responded with: “421 4.2.1 Unable to connect.” Attempted failover to alternate host, but that did not succeed. Either there Read more…