Thanks Don for your help. Since the one remote is gone, would it be best to just buy a new garage door opener? If I were to purchase new remotes, wouldn't the stolen one still work as well?
Thanks

I missed one sentence in your original post. You stated you changed the numbers on the garage door opener. I'm not sure I know what that means. Does your opener have dip switches that you changed? Or did you change the PIN number for your wireless keypad?

Anyway, if you purchase new remotes and then hold that button in for six seconds it erases all codes from the memory of your receiver. Then program everything except the remaining original remote. This will eliminate the stolen remote from working.

The responses here don't jive with my experience but maybe I'm missing something. But I have a Chamberlain, so maybe its different. When I pressed the learn button for 6 seconds (thereby resetting it), none of my remotes work until I then set a new code for each of them. What I would do before buying 2 new remotes would be to test what happens to the remotes after you clear the codes. Press and hold the learn button for 6 seconds till the lights flash. Test your remotes (don't set a new code for them). If they do not work, I would think that the stolen one also doesn't work. If you then set a new code for the remotes you DO have, theoretically only those remotes should work. But maybe there's something I don't know.

drmeow if you have older remotes with dip switches then what you say is true but they have been outmoded for years. If you have the newer remotes without the switches you are accomplishing nothing. You are erasing the memory of the receiver so that it doesn't recognize any code. Once you program it with the same remotes you are putting the same codes back into its memory. You haven't accomplished a thing.

Hi Don,

Thanks for the clarification. So I guess that means that the 2 remotes that came with my 1-year old opener have the same code? So, if I erase the memory of the receiver and then reprogram it with only one of those remotes, the other one would also work without me having to program it?

Not necessarily. They may have different codes from the factory. The receiver can learn and remember several codes. The model number of your opener looks something like this: 139.XXXXXSRT1 or 2. The SRT stands for "smart receiver technology". The more I know about these things the more I admire the engineers that design them.

If the remotes are rolling code type, resetting everything means the old units wil no longer work.
If you have the dip switch variety, changing the settings means the old one will no longer work.
The rolling code remotes are not on the same code path. The code reciever needs to be trained to recognize each and every remote. Once cleared, none of the rolling codes should work until you reload the ones you have. An unloaded unit wil not operate the door.
If you have smoe other technology, you should update it to rolling code for security. Every system I have seen has rolling code now. TI designed the chips and they are as cheap as dirt.

Came across this older thread and looking for some help.

I have the Sears Craftsman 1/2 hp opener m# 139.53919D 315 MHz.

Question- Can this opener learn codes from multiple different remotes?

I had one of the factory remotes stolen so I wiped the memory clean (holding the purple learn button) then reprogrammed an aftermarket remote I have (this has DIP switches inside it- so I changed the DIP settings) and it worked. Now the other factory remote I still have did not work, so I went through the learn process on it as well. Now they both work. The way I see it this opener learned a code from each transmitter, and the stolen one should now be useless. Am I right?

Thanks for any help on this.

Once you reset the opener, then all the remotes become useless until you reprogram them. The remotes "learn" from the opener, not the other way around. Basically the opener and remote(s) use a mathematical formula to generate a new code each time the button is pushed. When you reset the opener it generates a new "seed" for the formula and when you program the remote, the remote gets that new "seed" so it can generate the correct code in the sequence.