Basic Microsoft DOS troubleshooting

This page gives you a general overview of how to troubleshoot a computer while in MS-DOS or the Windows command line.

Messages encountered during boot

Before following the steps below, make sure that the error you are encountering is not already documented on Computer Hope. You can do this by performing a quick search for the error or by looking through our MS-DOS Q&A section.

  1. Ensure that your computer BIOS settings are correctly configured for the hardware that is installed in your computer. Improper settings in the BIOS may cause errors when first booting an IBM compatible computer. These errors often occur as the computer is first booting and may stop the load process of the computer.
  2. Errors that are encountered during boot are sometimes due to a misconfiguration with the autoexec.bat or config.sys files. We recommend that you edit your autoexec.bat and config.sys and look for any abnormalities. Additional information and help with the autoexec.bat and config.sys is availableon our autoexec.bat and config.sys page.

Other error messages

If you are experiencing other error messages, it is likely these errors are being caused by the software program you are running or a hardware device you are attempting to utilize. It is recommended you see the basic troubleshooting section for your hardware device or software program. If you are having errors running a command in MS-DOS, see the MS-DOS page for syntax of each of the MS-DOS commands and additional information about each of the commands.

Computer running slowly

  1. Make sure your autoexec.bat and config.sys are optimized. Changing the way programs load into memory, removing lines that are not necessary, and changing the order of lines in your config.sys can all help with improving the speed of your computer. See the autoexec.bat and config.sys page for additional information.
  2. Make sure your computer has at least 50 MB of free hard drive space. If your computer has less than 50 MB free, it may cause the computer to operate more slowly.
  3. Run Microsoft ScanDisk and Defrag on the computer. Additional information and help with these commands can be found on our ScanDisk and Defrag pages.
  4. From the MS-DOS prompt, type chkdsk /f . If this gives you a bad command or file name error message, type cd\dos and press Enter to get into the DOS prompt and try it again.
  5. Delete all the temporary files and any scandisk error files. From the MS-DOS prompt, type del *.tmp to delete all temporary files, then type del *.chk. Once the files have been deleted, type cd\dos to get into the DOS directory and delete the *.tmp and *.chk files as done earlier.
  6. Ensure your computer has the latest drivers for the hardware devices installed in your computer.

Issue with hardware device

If you are having difficulties with a hardware device, see the basic troubleshooting section for steps that can be taken to help resolve your hardware issues.


If you are still running into errors or cannot resolve your issue, you can search our web page, or check out our on-line help or Q&A sections for additional help. If after checking these locations, you are still unable to resolve your issue, feel free to contact our support team.

Additional information