MS Outlook stops working with sendmail/dovecot after upgrading to RHEL 6.5

Solution In Progress - Updated -


  • Why mail client MS outlook 2013 not working with sendmail smtp server after upgrade to RHEL 6.5 ?
  • Below error message appears.
Send test e-mail message: Your server does not support the connection encryption type you have specified. Try changing the encryption method. Contact your mail server administrator or Internet service provider (ISP) for additional assistance.
  • Other email clients work & also downgrading the openssl package to openssl-1.0.0-27.el6_4.2 works


  • Red Hat Enterprise Linux Server 6.5
  • sendmail-8.14.4-8.el6
  • openssl-1.0.1e-16.el6_5
  • ca-certificates-2013.1.95-65.1.el6_5

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