Sharp FO-6700 Operation Manual page 68

Sending a Fax by Automatic Dialing
To cancel a memory transmission
If you know the memory number assigned to a memory transmission,
you can cancel it with the following procedure. (If you don't know the
memory number, use the preceding procedure.)
1
Press the MEM. STATUS key (flip
up the Rapid Key overlay) and then 4.
The display will show:
4:MESSAGE CLEAR
ENTER MESSAGE #
2
Enter the 3-digit memory number
assigned to the transmission you want
to cancel.
3
Press the START key to cancel the
transmission.
66
MEM.STATUS
4
W
0 0 1
(Example)
START