The pages on this site contain documentation for very old MS-DOS software,
purely for historical purposes.
If you're looking for up-to-date documentation, particularly for programming,
you should not rely on the information found here, as it will be woefully
out of date.
Advanced Feature Unavailable
You are attempting to use a QuickBASIC feature that is
is available with another version of BASIC or supported
only under a later version of DOS or OS/2.
ERR code 73