General Tips for Using MS-DOS Mode

ID: Q134400

The information in this article applies to:
  • Microsoft Windows 95
  • Microsoft Windows 98

SUMMARY

You can use MS-DOS mode in Windows to run MS-DOS-based programs that require exclusive use of all your computer's resources. This article contains tips on how to configure MS-DOS mode.


MORE INFORMATION

Windows normally uses MS-DOS mode when it detects that a program requires it. If the program you want to run is not recognized by Windows, you receive an error message stating that the program cannot be run within Windows. You can then manually configure the program to use MS-DOS mode.

Once you configure a program to use MS-DOS mode, double-clicking the program's icon causes Windows to switch to MS-DOS mode automatically.

Before switching to this mode, Windows ends all running tasks, loads a real-mode copy of MS-DOS, and loads customized Autoexec.bat and Config.sys files if appropriate. When MS-DOS mode loads, you see the following message:

Windows 95/98 is now starting your msdos based program.
When you exit MS-DOS mode, Windows restarts.

Configuring MS-DOS Mode

To configure an MS-DOS-based program to run in MS-DOS mode, you should have a shortcut icon for the program. If there is no shortcut icon for the program, use the right mouse button to click the program's icon, and then click Create Shortcut on the menu that appears. Once there is a shortcut icon for the program, follow these steps to configure the program to use MS-DOS mode:
  1. Use the right mouse button to click the shortcut icon, and then click Properties on the menu that appears.


  2. On the Program tab, click Advanced.


  3. Click the Prevent MS-DOS-based programs from detecting Windows check box to select it.


  4. Click OK.


  5. Try to run the program by double-clicking its shortcut icon. If the program runs, stop here. If the program still does not run, continue with these steps.


  6. Use the right mouse button to click the shortcut icon, and then click Properties on the menu that appears.


  7. On the Program tab, click Advanced.


  8. Click the MS-DOS Mode check box to select it.


  9. Click OK.


  10. Try to run the program by double-clicking its shortcut icon. If the program runs, stop here. If the program still does not run, continue with these steps.


  11. Use the right mouse button to click the shortcut icon, and then click Properties on the menu that appears.


  12. On the Program tab, click Advanced.


  13. Click the Specify A New MS-DOS Configuration option button. This option lets you specify a custom Config.sys and Autoexec.bat file for the program. The custom configuration is in effect for this program only.


Specifying a New MS-DOS configuration

To change the configuration to suit the program, follow these steps:
  1. Review the lines in the Config.sys For MS-DOS Mode and Autoexec.bat For MS-DOS Mode boxes. Make any necessary changes directly in the boxes.

    NOTE: If you must add a driver or program for every MS-DOS based program you run, create a new file called Dosstart.bat in the Windows directory. Add the driver or program to this file.


  2. If a program does not run or performs poorly because of insufficient memory or the lack of a driver, click the Configuration button to choose the options you want for the program. To learn the purpose of each option, click the option's text and then read the description. Click the options you want, and then click OK.

    NOTE: Using these options removes any entries you may have already made in the Config.sys For MS-DOS Mode and Autoexec.bat For MS-DOS Mode boxes.

    WARNING: Although some MS-DOS-based programs require direct disk access, most do not. Use this option with caution. Using this option can allow an MS-DOS-based program to destroy long filename support in Windows.


For more information about configuring an MS-DOS-based program, consult the program's documentation.

For additional information, please see the following article in the Microsoft Knowledge Base:
ARTICLE-ID: Q77083
TITLE: Optimizing Your Use Of Upper Memory Blocks

Default Changes to Configuration Files

When you start MS-DOS mode, new Config.sys and Autoexec.bat files are created. The following lines are added automatically by Windows:

The first line of the Config.sys file: 

   DOS=SINGLE

The last lines of the Autoexec.bat file: 

   REM
   REM The following lines have been created by Windows.
   REM Do not modify them.
   CD \<directory of the application>
   CALL <name of application>
   <Windows>\WIN.COM /WX

The line "DOS=SINGLE" causes your computer to start in MS-DOS mode. The "Call" line starts the MS-DOS-based program. The "WIN.COM /WX" command restarts Windows with the normal configuration.

Troubleshooting

  • Windows does not restart after you quit the MS-DOS-based program.

    Type win /w at the command prompt to restart Windows.


  • The program does not run in MS-DOS mode because of an incorrect configuration.

    Add the appropriate lines in the Advanced Program Settings dialog box.



REFERENCES

For additional information about the process that occurs when you restart your computer in MS-DOS mode, please see the following article in the Microsoft Knowledge Base:

ARTICLE-ID: Q138996
TITLE : Description of Restarting Computer in MS-DOS Mode

For additional information about games that require or perform better in MS-DOS mode, please see the following articles in the Microsoft Knowledge Base:
ARTICLE-ID: Q132994
TITLE : Games (A-H) Requiring or Performing Better in MS-DOS Mode

ARTICLE-ID: Q132995
TITLE : Games (I-Q) Requiring or Performing Better in MS-DOS Mode

ARTICLE-ID: Q132996
TITLE : Games (R-Z) Requiring or Performing Better in MS-DOS Mode

Microsoft Windows 95 "Resource Kit," Chapter 22, Application Support

Additional query words: pif

Keywords : kbenv win95 win98
Version : WINDOWS:95
Platform : WINDOWS
Issue type : kbinfo


Last Reviewed: May 26, 1999
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