Battery Bar No Longer Appearing, used to be fine.

An issue I've been having for a while is my battery bar no longer appearing.
My battery bar worked for several months, from the time I installed a Windows 7 partition on my laptop, but all of a sudden it just went and disappeared. In the customize notifications/settings window, I can't check to show Battery Life, it's grayed out. I tried all sorts of registry fixes for this and went into the registry, but nothing fixed it. I also tried third-party battery monitoring software and none of that worked as well.

Anyone have a fix for this? I resorted to using Windows 8 (upgraded to 10) and I'm having issues with that as well, so I'm trying to get the battery issue fixed and just use Windows 7 again.

Any solutions are welcome.

From what you said, it's 2 partitions on your computer? If so, what's the Main OS, it may be something there causing the problem.

The main OS is Windows 10 (upgraded from Windows 8)
The battery bar was appearing before, though, and I wasn't even using the Windows 8 partition when the battery bar stopped appearing. One day it just up and disappeared and I can't figure out how to restore it.

It's grayed out, as I said. I can't re-enable it.