I followed the Q from the start just to see if anyone would come up with surefire remedies, because I sure don’t know of any.
I think @Lightlyseared has the best idea. “Security” on most personal computers is a moving target. What works in some offices (on some computers) and with some people won’t be effective elsewhere. I don’t know about Office 10, for example, but if you have a file that is “password protected” in Excel, I can probably open it as quickly without the password as you can with it. Maybe that has been improved.
Microsoft Access, on the other hand, has somewhat better security. But if I want to spend the $5 for a shareware program on the Net (which I have already tested and verified in its “free” version), I can get into that, too.
If you want it to be private, keep it to yourself.