On the bright side, this only has to be done once!
Here’s where things really start getting sloppy. The developers had neither the confidence in their shutdown code, nor the foresight about a missing installation step needed to make this easy. If you want your UPS to turn off after your computer shuts down during a blackout, and then turn back on when the power is restored, you have to change this registry value. It’s located at HKLM\System\CurrentControlSet\Services\Apcupsd\ImagePath and all you have to do is add “-p” on to the end of it. This also makes you familiar with what to erase if your UPS starts turning off at the wrong time.