I just programmed my Sony VL600 to control my Harmon Kardon AVR-135. The power button will now turn it on but not off. The remote that was supplied with the reciever has an ON button and an OFF button. Am I going to have to program another button on my Sony to turn the unit off or can I somehow use the power button for both on and off. Thank you for the help.

The sony remote will not give you something that HK oem remotes never have had, a power toggle. You will have to teach the second command to another key.