We were given a 20-year old Compaq Portable II, with a very old version of DOS. We are getting a mesage of "Bad or missing command interpeter" when we start the computer. If anyone could help us get this old thing going, we would appreciate it. (We are no longer intimately familiar with DOS, so please remember that in your responses). Thank you, Alan

It means that COMMAND.COM is missing or damaged. If you have a bootable diskette of that version of DOS, reboot with that diskette and copy COMMAND.COM to C: If you don't have a boot diskette of that version, use the boot diskette of any DOS version and look if there is COMMAND.COM in the directory C:\DOS Type: DIR C:\DOS\COMMAND.COM If the result isn't "File not found" or something like that, type: ECHO SHELL=C:\DOS\COMMAND.COM C:\DOS\ /P>>C:\CONFIG.SYS and reboot your computer.

note that what he told you to type was all on one line. Also note that you may have disk errors causing the problem rather than just a missing file, i suggest running scandisk beforehand.

You need a bootable DOS floppy disk that contains these files: FDISK, FORMAT and SYS. If it's bootable then it is assumed that you have COMMAND.COM on it. After you boot to the floppy disk you need to run the SYS program. Type SYS C: and if it says system files copied then remove the floppy and restart your computer. If it gives you an error message about not being able to write to drive C: then you should run FDISK. This is the hard drive partitioning software. If you don't know how to use FDISK I suggest you get a DOS manual, (any version). Once the harddrive is partitioned correctly you will need to format it. This is done by typing FORMAT c:/S - the /S tells it to copy the DOS operating system, (boot files), to the hard drive.