uAdmin

Mail server

Mail TLS and common issues

Per-domain certificates, webmail SSO, Outlook SSL warnings and checks after OTA updates.

  1. TLS certificate

    Mail → Server settings → Issue/Renew certificate. The panel uses Let's Encrypt DNS-01 and includes mail.{domain} and webmail.{domain} in SAN for each virtual domain. The cert is deployed to Postfix, Dovecot and Apache (webmail).

  2. Outlook / certificate warning

    If Outlook reports «target principal name is incorrect», the certificate does not include mail.{your-domain}. Renew TLS from the panel after adding the domain. Antivirus (e.g. Avast Mail Shield) may intercept the connection — test with interception temporarily disabled.

  3. Webmail SSO

    Always use «Open webmail» from the panel. If you see «Connection to storage server failed» or «session expired», close the tab and open webmail again from the panel (a private window helps). After OTA re-apply Roundcube and Connector install steps on the mail VM.

  4. After panel OTA

    OTA updates panel code but does not automatically change the mail VM. In Mail → Settings → Re-apply: Dovecot, Firewall, Roundcube, Connector. Then renew the TLS certificate if you added new domains before OTA.