I'm getting this error while trying to send external mails on exchange server 2013
i can receive mails normally and send internally but cant send externally
'441 4.4.1 Error encountered while communicating with primary target IP address: "Failed to connect. Winsock error code: 10051, Win32 error code: 10051." Attempted failover to alternate host, but that did not succeed. Either there are no alternate
hosts, or delivery failed to all alternate hosts.