Thanks to both of you who have helped me. I appreciate it very much. Finally, following JLET's step-by-step guidance, the 550 WORKS !!!! Never, in a thousand years, would I have guessed that I had to try all of the 15 pages of inputs on the 550 remote for the DEVICE, write down the ones that work directly, make up a list of names, specify that I do NOT have the original Mitsubishi remote, and go through a list of commands to teach the 550 how to select the names that I chose. Why on earth would the Logictech software require me to state that I do NOT have the OEM remote? I don't know if either AKIRBY or JLET works for Logitech, but if so, I think you should work with the company to change the webpage and the software so that an ignoramus (like me) can discover on his own that I have to specify that I do NOT have the OEM remote and then go through all the gymnastics required to program the remote. It just does NOT work to have people who know what they are doing write the software for people who know what they are doing. AGAIN ---- thanks and thanks to both of you !