Thanks for reporting this problem.
Are you able to reproduce the problem if you save only that message to the same target folder?
Please send a screen shot of the error to firstname.lastname@example.org, along with the full message subject line and the Message Saver configuration file. You can find the file, Message Saver_Flexalock.INI, at the location similar to this:
C:Documents and Settings[Windows User Name]Local SettingsApplication DataAdvansysFormativ1.0Config
We look forward to your reply.