Markus Hess exploited a security flaw in GNU Emacs' email subsystem in his 1986 cracking spree in which he gained superuser access to Unix computers.
Whereas many Windows programs assume the user is an administrator—something very prevalent in the days of Windows 95/98/ME (and to some degree in Windows XP/2000, though not in Windows Vista or Windows 7)—such would quickly result in "Permission denied" errors in Unix-like environments since users will be in an unprivileged state much more often.
In Microsoft Windows 2000, Windows XP Professional, and Windows Server 2003, there is a "Power Users" group on the system that gives more permissions than a normal restricted user, but stops short of Administrator permissions.