outgoing twc email messages wont go through

The names of the services are used in the next step. Verify the services that are associated with the TLS certificate. In the Send connector logs, look for the thumbprint of the TLS certificate. To do this, run the following command: Set-SendConnector '' -ProtocolLoggingLevel Verbose

To do this, follow these steps:Įnable logging on the Send connector.

To resolve this issue, bind the third-party certificate to the SMTP service. This issue occurs if a third-party certificate that is installed on the server that is running Exchange Server is not bound to the SMTP service. TLS negotiation failed with error UnknownCredentials. Either there are no alternate hosts, or delivery failed to all alternate hosts.Īdditionally, the following entry is logged in the Send connector logs if logging is enabled: When you examine the status of the queue, you notice the following error message:Ĥ51 4.4.0 Primary target IP address responded with: '421 4.4.1 Connection timed out.' Attempted failover to alternate host, but that did not succeed.

Outgoing twc email messages wont go through