I really need your help. My Craftsman unit model number is 139.53615SR manufactured 1/92. There are no dip switches, only a smart button with a red light. I have not had any problems with the door. The original two remote controls were lost and since then I've used the setting in my car to open the garage. I decided to purchase new remotes. Last week I purchased a Chamberlain Clicker, KLIK1U. I was able to complete the learn process with Clicker, but then discovered my neighbor was also able to open and close my garage door. Friday, I went to Sears and purchased Craftsman remote # 53778. The learn process worked but the neighbor could still open the door. I returned those yesterday and purchased Craftsman remote #53879, which of course don't work as they are for units with a green smart button and mine is red. It is very troubling being in my home and not knowing when the door will open. Today I posted on fixya.com and was told to hold the learn button after the neighbor opened the door to erase the codes. Afterwards, the code in my car was erased. I was able to get the remote # 53778 to work and reset the car, but my neighbor can still open and close the door. My neighbor is helping and trying to remember to close the door when he notices it but that is clearly not the solution. Any guidance is appreciated. Thanks.