Dear All Have you any idea about this: 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 are no alternate hosts. or delivery Failed to all alternate hosts

did you run get-queue <queueID> | fl ? and the last error may be what you have posted above. i have seen this happening when the target server is facing performance issue and is not accepting messages due to backpreasure, other reason may be authentication settings on the recieve connector on the targer server start by looking on the application logs on the target serverDhruv