I have used a Long Ranger III to control my dust collector for several years. Yesterday when I pressed the on button of the remote nothing happened. So I took the battery out and took it in the house and tested it--it was dead. I replaced the battery and took it back and nothing happened when I pushed the button. So I went out and checked the dust collector and it started up fine when I plugged it into the outlet. I said to my self, the Long Ranger has died. Before ordering another one I raised the hood to see what was fried inside. It looked fine. Then I saw a little black button I had not noticed before. It said it was to synchronize the remote signal with the box push the button then press the on or off button within 5 seconds. I put it all back together, plugged it in and synchronized the remote. Now it works again. I surmise that changing the battery changed the remote code. That battery was the original one and was not even an alkaline battery.
At my age you learn the same things over and over.