You cannot alter this property after the message has been sent.

• Setting up SQL applications
• ml_qa_getstringproperty
• ml_qa_createmessage
• ml_qa_getmessage
• Custom message properties

In the following example, a message is created, the string properties mystringproperty1 and mystringproperty2 are set, and the message is sent to the address clientid\queuename:

begin
    declare @msgid varchar(128);
    set @msgid = ml_qa_createmessage();
    call ml_qa_setstringproperty( @msgid, 'mystringproperty1', 'c:\\temp' );
    call ml_qa_setstringproperty( @msgid, 'mystringproperty2',  'first line\nsecond line' );
    call ml_qa_putmessage( @msgid, 'clientid\queuename' );
    commit;
end