A device attached to the system is not functioning

Updated: 01/24/2018 by Computer Hope

Error when trying to start an MS-DOS session


If you are experiencing issues or errors when starting an MS-DOS session, follow the steps below.

  1. Extract the file Winoa386.new from the Windows cabinets to the Windows\System directory. Depending on what operating system you are using, the location of this file may vary on the CD. Below is a listing of cabinets that hold this file, based on the operating system.
  • Windows 98 CD-ROM = Win98_45.cab
  • Windows 95 OEM CD-ROM = Win95_03.cab
  • Windows 95 DMF floppy diskettes = Win95_03.cab (Disk 3)
  • Windows 95 non-DMF floppy diskettes = Win95_04.cab (Disk 4)
  1. Boot to a bootable floppy diskette or boot the computer to MS-DOS.
  2. Once at the MS-DOS prompt, run the following commands:
ren winoa386.mod winoa386.ch
ren winoa386.new winoa386.mod
  1. Reboot the computer.

Error when trying to run a Visual Basic 3.0 program in Windows

If this issue is occurring when attempting to run a Visual Basic 3.0 program, delete vbrun300.dll from the Windows\System directory and re-copy a new version of this file to the directory.

For download links related to vbrun300.dll, see the Windows DLL section of our downloads index.

Additional information