Thank you to Beta for your advice.
I tried as suggested - clicked the Start button on bottom Left corner, then the RUN option shown. I typed in as suggested but nothing.
I can confirm that MSN have now replied, & I have now Reset my own password - this lets me access MSN 7.5 as normal.
I've followed the Help advice given on the Help option on the initial 7.5 Sign-in window, but it does NOT work -
I add my girlfriends email address, then my own password (as that is the only one I have)
The Error Message shows - the sign-in name does NOT exist, or, the password is incorrect.
Advice from anyone would be welcome