Epson Apex 20020 - Manual (Page 142)

The CHKDSK program can recover data that has been
inadvertently lost on the diskette. It makes changes to the
diskette if you use the
/F
switch in the command like this:
CHKDSK A: /F
See the description of CHKDSK in your MS-DOS
Reference Manual before making corrections to the
diskette.
Diskette Drive Problems
Follow these steps if you are having difficulty with a diskette
drive:
1. If the diskette is not turning or the diskette drive is making
loud noises, do not attempt any further examination of it.
Instead, contact your Epson Customer Care Center.
Note
Diskette drives may make different sounds with different
diskettes.
2. If your diskette drive read/write heads are dirty, you may
occasionally see this MS-DOS error message:
Error Reading Drive d
Abort, Retry, or Fail?
To clean the read/write heads, use a diskette head cleaning
kit. Such kits are available in most computer stores.
3. If you are still having problems with your diskette drive, try
running the Floppy Disk Drives and Controller Check
described in Appendix C of this manual. If the diagnostics
program indicates an error, consult your Epson Customer
Care Center.