Association does not imply execution. For example, I have an association setup for .a23 files, however all the association does is make it so an icon is displayed for a23 files, if I click the file I get the standard "select a program" dialog box. File associations do not determine whether a file can be executed. And opening a file doesn't test a lock. I can lock bytes 23 through 29. Opening it will succeed, however when I try to read bytes 23 through 29 that will fail.
