I have a clicker model KLIK2U and forgot the code. How do I reprogram without the old code?

It's really easy to reprogram your unit:
Step 1. Hold down the (*) and the (#) keys until the keypad stops flashing.

Step 2. Determine your opener ID using the list below:

*1= linear garage door openers manufactured from 1997 to
present.

*2= Chamberlin, Sears, Craftsman, LiftMaster, Master
Mechanic and Do it garage door openers manufactured from
1997 to 2004 ( Orange learn Button)

*3= Same as *2 above, but manufactured from 2005 to present
with a (Purple learn Button)

*4= Same as *2 above, but manufactured from 1993 to 1996
with a (Green learn Button)

*5= Genie Intellicode and Overhead Door garage door openers
manufactured from 2005 to present (315 MHz).

*6= Same as *5 above but manufactured from 1995 to present
(390 MHz).

*7= Stanley garage door openers manufactured in 1998 to
present.

*9= Wayne Dalton garage door openers manufactured
in 1999 to present.

Openers with learn Buttons

Programming: Enter the PIN that you want to use, remember
(4) digits only. then press #

Enter ID # from list above, for example 2 then #

Press and release the Learn button on your
garage door opener.

Enter your (4) digit PIN and press (0),
for Genie and Overhead door units press
(0) twice. To test and use wait for light to go out
on keypad, Enter you PIN and press (0).
Note: If opener doesn't function repeat programming.

From: Cybersensi@aol.com for further
Instructions if required.