Published: July 16, 2012
Applies to: Exchange 2013 | Exchange Online | Exchange Server 2010 Service Pack 1 (SP1)
The ContainsHeaderStrings element indicates the strings that must appear in the headers of incoming messages in order for the condition or exception to apply.
The following sections describe attributes, child elements, and parent elements.
Represents a string that must appear in message headers in order for the condition or exception to apply.