Tommy said:
The United States District Court has ruled that software purchasers may make fully functional backups of their software, even if that software was copy-protected.
The United States District Court has ruled that programs which defeat copy protection are legal since they have an acceptable legal use in making archival backups of copy-protected computer software.
No problem legally about making a copy for back-up purposes nor in circumventing the copy protection
so long as you don't modify the program.
You cannot, however, modify the program (i.e. use a crack) and use the modified program without the permission of the author/copyright holder irrespective of anything in the EULA (and somehow I just don't think you'll get that permission

even if you're silly enough to ask

).
[The only real exception to this is for open-source soft, but, of course, open source soft ain't copy protected.]