Exchange meeting requests do not work correctly when passing through MailMarshal


This article applies to:

  • Trustwave MailMarshal (SEG)
  • Exchange Server

Symptoms:

  • MailMarshal scanning messages between Exchange Servers.
  • Exchange meeting requests arrive as plain text and are not processed correctly at the receiving server.

Causes:

  • MailMarshal message stamping can cause this issue.
  • The issue does not occur with every combination of Exchange server versions.
  • The issue is more likely to occur when messages are stamped at the top.

Resolution:

To resolve this issue, you can create a TextCensor rule to avoid stamping meeting requests.

  • First create a TextCensor script to recognize the messages. For requests originating on Exchange Server 2007, you can create a script similar to the following:

Apply to: Message Body
For older versions with "special character" matching, enable matching of special characters.

  • In the list enter : (the colon character)

Weighting Trigger Level: 25

Enter the following 5 items with weighting level 5, Standard weighting:

BEGIN:VCALENDAR
END:VCALENDAR
PRODID:Microsoft Exchange Server 2007
ORGANIZER
ATTENDEE

  • Next create a rule that applies this script to skip message stamping. For instance, if you use a single rule to stamp messages, you can create a rule like the following:

When a message arrives
Where message is outgoing
Where message triggers text censor script(s) 'No stamp for meeting requests'
Pass the message on and skip the next rule

  • Place this rule immediately before the message stamping rule.

To apply the change, commit configuration.

 


Last Modified 3/1/2020.
https://support.trustwave.com/kb/KnowledgebaseArticle12881.aspx