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MAILCONTLS - Secure Connection (SSL/TLS) Failure

Error CodeMAILCONTLS
Error MessageSecure connection to the mail server failed. Please check the security type and security certificate.
SeverityHigh
AffectsIncoming and Outgoing Email Servers

Symptoms​

  • The connection attempt fails during the SSL/TLS handshake stage.
  • Test Connection returns a certificate or secure-connection failure.

Root Cause​

  • The Security Type or Port doesn't match what the mail server requires.
  • The mail server has an expired or untrusted SSL certificate.

Resolution​

  1. Navigate to Admin > Support Channel > Emails and open the affected server.
  2. Verify the Security Type and Port are correct for your mail provider. Most providers require SSL or TLS — confirm which one your provider expects.
  3. If you're using an internal company mail server, verify that the security certificate is valid and not expired.
Related FAQs

See Email Server FAQs for: "Why is the incoming email server not fetching any emails?" and "Why are all outgoing emails failing with a connection error?"