Dos displays an error message like abort whenever it has trouble using one of your disks or files. This is one of the most common DOS error messages you will see, and to fix it you first have to understand why DOS is complaining.
1. If you get the error message when you’re trying to use a floppy disk, first be sure that the disk is all the way in the disk drive, and that the drive door (if there is one), is closed.
2. If you tell DOS to switch to a floppy disk (by typing, say, B: followed by the Enter key), but there’s no disk at all in the floppy drive, you’ll get an error message.
3. If the error message appears when you’re trying to copy or open a file, it probably means that DOS is having trouble, big trouble, reading the information on the disk. You may have lost some of the file, but maybe not all of it.