Epson 386/25 - Manual (Page 236)

Caution
If you are unsure if formatting is necessary, contact your
Epson dealer for assistance.
In addition to destroying all the data on the hard disk,
formatting removes any partitions and logical formatting defined
on the disk by FDISK, SELECT, or FORMAT. After you
physically format a new or used hard disk (using option 1 or 2 of
the Hard Disk Format Menu), you need to install MS-DOS.
Follow the instructions in your MS-DOS Installation Guide.
The installation process automatically partitions and formats the
hard disk to prepare it for use. (If you are installing another
operating system, follow the instructions in the documentation
that came with it.)
Choosing the Type of Format
Follow these steps to display the formatting options:
1. Insert the Reference diskette in drive A.
2. Turn on or reset the computer. The computer automatically
loads MS-DOS and displays the Operation Menu.
3. Press 2 to highlight Format hard disk and press
Enter. The Hard Disk Format Menu appears on the screen:
HARD DISK FORMAT MENU
1 - Format
2 - Destructive surface analysis
3 - Non-destructive surface analysis
0 - Exit
C-2 Physically
Formatting a Hard Disk