Microsoft KB Archive/40636

From BetaArchive Wiki
Knowledge Base

Why QuickBasic Might Hang; Hardware or Software Conflicts

Article ID: 40636

Article Last Modified on 11/21/2006


  • Microsoft QuickBasic 1.01
  • Microsoft QuickBasic 1.02
  • Microsoft QuickBasic 2.0
  • Microsoft QuickBasic 2.01
  • Microsoft QuickBasic 3.0
  • Microsoft QuickBasic 4.0
  • Microsoft QuickBASIC 4.0b
  • Microsoft QuickBasic 4.5 for MS-DOS
  • Microsoft BASIC Compiler 6.0
  • Microsoft BASIC Compiler 6.0b
  • Microsoft BASIC Professional Development System 7.0

This article was previously published under Q40636


This article provides a list of possible software and hardware conflicts that may cause a program to hang (in the QB.EXE editor or in an executable .EXE program). To determine why a program might hang, the possibilities below should be checked.

If the steps below are followed and the program still hangs, the problem may be related to a coding error or a problem associated with QuickBasic itself.


The following are potential software conflicts:

  1. Terminate-and-stay-resident (TSR) programs. QuickBasic is not designed for use with most TSRs and does not support them. Remove these programs and reboot the computer without loading the TSRs.
  2. Networks. Unsupported networks fall into the same category as TSRs, and they should be removed. (However, there should be no problem with the IBM PC Network or MS Network, both of which are supported.)
  3. Operating systems. Always use the standard operating system provided by the manufacturer of the computer. QuickBasic is not supported under multiuser or multitasking operating systems. Try using the standard PC-DOS or MS-DOS with the computer.
  4. Extended/expanded memory. QuickBasic does not use either extended or expanded memory, and the drivers that provide this support should also be removed from the system.

Note: To ensure that there are no programs loaded in memory in all the cases above, use the original DOS disk provided for the computer by the manufacturer. There should be no special DEVICE=xxx.SYS statements in your CONFIG.SYS file and no special programs installed by your AUTOEXEC.BAT file.

The following are potential hardware conflicts:

  1. Incorrect math-coprocessor settings. If the math-coprocessor switch settings are incorrect, QuickBasic may hang. By using the command "SET NO87=xxxx" at the DOS prompt, you inform QuickBasic not to use or check for the math coprocessor. If QuickBasic then works correctly, the switch settings may be incorrectly set. For more information on the correct switch settings, query on "NO87" in this Knowledge Base.

    Also, the speed of the coprocessor must be equal to or less than the speed of the computer's CPU (central processing unit); otherwise, a numeric exception error can hang the machine.
  2. Video systems. The computer's video system should be a standard video system (CGA, EGA, VGA, or MONO-TEXT). There are several options available for checking the video system. Proper configuration of the video hardware can be performed by issuing three MS-DOS MODE commands, as follows:


    If QB.EXE Version 4.50 does not operate with your video system, try invoking QuickBasic with each of the video-specific options, such as the /b (black and white) option, the /nohi (no high-intensity) option, the /g (update screen as fast as possible) option, and the /h (high-resolution) option. For more information, query on the words compatibilities and QuickBasic in the Microsoft Knowledge Base.

Additional query words: QuickBas BasicCom

Keywords: KB40636