Important Notice

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documentation, particularly for programming, you should not rely on the information found here, as it will be woefully out of date.

■ More than one condition can cause this error:
 
  • You tried to perform:
    ♦ An ISAM operation without the correct ISAM TSR loaded
      (PROISAM or PROISAMD).
    ♦ FRE(-3) when no expanded memory is available.
 
  • You tried to use a feature of:
    ♦ Another version of Basic that is not available with
      this version of Microsoft Visual Basic for MS-DOS.
    ♦ Microsoft Basic that is unavailable under the
      operating system you are running (for example, using
      the LOCK or UNLOCK statement while running MS-DOS
      version 2.1).
 
■ If you need additional help, move the cursor to a keyword
  and press F1 to open the Help window.