VERIFIED SOLUTION i

How to populate the 'Transaction ID' field, position 78-89 in the version 1.6 Shipping Services File (SSF) in MailStream Plus?

MailStream Plus does not support that at this time.  It must be a Unique Id that currently the User needs to populate with a post-MSP process.

(Enhancement requests can be submitted for this to be added to the software.)
UPDATED:  April 21, 2017