Specify the protocol to use with TLS in version 7.2.3 and below


This article applies to:

  • Trustwave MailMarshal (SEG) 2006 (release 6.2 through 7.2.3 only)
  • For release 7.3 and above, see Q19541. 

Question:

  • How can I specify a protocol to use for TLS?

Procedure:

TLS or Transport Layer Security is a method of creating a secure connection between servers over which email can be transported. 

Note: For basic information about using TLS with MailMarshal SMTP, see Q11636: How Do I Set Up TLS in MailMarshal SMTP?

MailMarshal can use the following protocols when establishing a TLS connection:

  • TLSv1
  • SSLv2
  • SSLv3

By default, when receiving email, the older MailMarshal versions that this article applies to allow any of the three protocols, including TLSv1.

In MailMarshal SMTP 6.2 and above, you can specify the protocol MailMarshal uses when receiving email. You can specify the protocol separately for each server in an array.

To specify the protocol:

  1. Edit the Registry on the MailMarshal Array Manager.
  2. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Marshal\MailMarshal\Default\Servers\<servername>
    • For full details of the location for each version, see article Q10832.


    Example: HKEY_LOCAL_MACHINE\SOFTWARE\Marshal\MailMarshal\Default\Servers\MailNode01

  3. Add a DWORD value named SSLMethodType. Enter a value from the following list:

    Value

    Protocols Allowed

    0

    TLSv1

    1

    SSLv2

    2

    SSLv3
    TLSv1

    3

    SSLv2
    SSLv3
    TLSv1
    (This is the default option)
  4. Add the value for each server that uses TLS.
  5. To apply the Registry changes to the email processing servers, commit configuration and then restart the Receiver service on each server.

Warning: Using the Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Trustwave cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Make sure that you back up your Registry prior to making any changes.

Notes:

TLS settings are controlled by the receiving server.

  • SSLv23 (the default option for inbound TLS) is the most compatible option. This option indicates that any of the three protocols is acceptable.
  • If you specify an option that the sending server does not support, the TLS negotiation can fail. In some cases, you could be unable to receive email from a domain.
  • When MailMarshal sends email using TLS, the protocol used depends on the settings of the other server.  However you can force the MailMarshal Sender to use only TLSv1 by the following method:


    1. Edit the Registry on the MailMarshal Array Manager.
    2. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Marshal\MailMarshal\Default\Sender
    3. Add a DWORD value named UseTLSv1
    4. Set the value to 1
    5. Commit configuration, and then restart the Sender service on all servers.

Last Modified 4/1/2020.
https://support.trustwave.com/kb/KnowledgebaseArticle11675.aspx