Outlook unexpectedly AUTOSAVES to my Boilerplate.msg file

Hi,

I have a number of Outlook Boilerplate.msg files that are preconfigured for various correspondence requirements.

When I modify the boilerplate HEADER + MESSAGE body, then send it off to recipient, Outlook performs as expected (and does NOT update the original boilerplate.msg file).
...but ...
As soon as I ATTACH a file, then send it off to recipient, Outlook UPDATES the original boilerplate.msg file (defeating the purpose of having a saved ORIGINAL boilerplate).

Here is what I have tried so far to no avail:
1) Options|Mail|Save Messages|UNCHECK Automatically save items that have not been sent
2) Options|Mail|Save Messages|CHECKMARK Automatically save items that have not been sent after this many minutes = 99

As a work around I have been using a pristine boilerplate_BAK.msg to overwrite the compromised boilerplate.msg. This is a very cumbersome approach since I use boilerplates extensively.

PLEASE HELP me with a better solution.

THANX... Frank