Epson 10020 - Manual (Page 122)

If you have the optional 720KB drive, use 3 1/2-inch
double-sided, double-density diskettes. You cannot use
3 1/2-inch diskettes that were formatted for 1.44MB in
this drive.
4. If your diskette is the right type for your drive, check to see
if the diskette is write-protected. There may be a write-
protect tab over the notch on the side of the diskette
(5 1/4-inch) or the write-protect switch may be set (on a
3 1/2-inch diskette). You cannot store or revise data on a
write-protected diskette. See Chapter 2 for information on
write-protecting diskettes.
Some application programs do not function properly if the
diskette is write-protected. Check the program manual.
5. If MS-DOS displays errors when you try to access data,
your diskette may be defective. MS-DOS error messages
that may indicate a defective diskette include these:
Disk Drive Error: Abort, Ignore, Retry?
Disk error reading drive d:
Disk error writing drive d:
If you see one of these messages, make sure the diskette is
properly inserted in the diskette drive and the diskette
drive latch is closed. Try the operation again. If the
problem persists, try removing the diskette and reinserting
it. This may solve the problem if the diskette was not
seated properly in the drive.
Is the diskette formatted? A new diskette must be
formatted before you can store data on it. See Chapter 3 for
instructions on formatting diskettes.
If the error message still occurs, you probably have a
defective diskette. Use the MS-DOS COPY command to
copy the files from the diskette onto another diskette. (See
“Copying Diskettes” in Chapter 3 for instructions.)
5-6 Troubleshooting