Login to Blackboard Learn as administrator

Go to the administrator email configuration area for outgoing email or SMTP relay settings.

Select the option to use a custom Customer E-Mail Relay or custom SMTP relay

Enter a custom SMTP hostname for the relay

Enter a non-default SMTP port, for example the port required by the customer relay instead of port 25

Select an SSL/TLS option, such as STARTTLS or SSL/TLS, based on the customer relay requirement

Enter the SMTP username and password if authentication fields are available

Save the email relay configuration.

Trigger an outgoing email from Blackboard Learn, such as a test notification, course message, or system email

Review the mail connection behavior or mail logs.

Confirm the issue reproduces if Blackboard Learn attempts to connect using port 25 without TLS instead of the configured port and SSL/TLS settings.