There is a plethora of info regarding programming of Homelink on t'internet but not quite the problem I'm having at the moment. My Homelink was trained perfectly to the first channel of my remote and then synchronized with the rolling code in channel one of the receiver. So far, so good. The Homelink then trained perfectly to the second channel of my remote using one of the unused Homelink buttons, producing the characteristic rapidly flashing light. However, it will not synchronize with the rolling code from the receiver, no matter what I try. I have the same problem if I completely delete the links in both Homelink and the receiver and then try using different Homelink buttons as the first and second channels. From this, I deduce that all the Homelink buttons are active and programmable. Unfortunately, I cannot fathom why I should be having difficulty synchronizing a second button. Does anybody have any clue please? Or is there an alternative method of synchronizing? I followed the instructions in the manual and the first channel worked perfectly. I've tried various combinations of the number and duration of Homelink button presses. Please, can anybody assist? Thank you