Epson LT-286 - Manual (Page 60)

Booting From the Hard Disk
Now you can boot your system (load MS-DOS) from drive C. Just
make sure there is no diskette in drive A when you turn on or reset
your computer.
Turn off the computer, wait at least five seconds, then turn it back
on. After the computer completes its power-on self test, the screen
displays the date prompt. Press
Enter twice to accept the date and
time shown.
The
C>
prompt appears, indicating that the system has successfully
loaded MS-DOS from your hard disk.
From now on, each time you turn on or reset your computer, it
automatically loads MS-DOS from the hard disk. Just make sure
drive A is empty.
3-12 Preparing the Hard Disk for Use