Boot Camp partition is on lowest brightness and will not change It all started this morning, since I listen to podcasts on YouTube before bed. I barely use my Mac partition, but still update it. I use my Windows partition for most of my stuff.

I went to bed with the screen dimmed all the way down and went to sleep. When I woke up, my computer was shut down but still perfectly fine. I started up Windows and after the "Starting Windows" screen, the screen went black since it is dimmed all the way down and now I can't brighten it back up.
Just point a small torch (I used the one in my old mobile phone) to the windows screen where it requires your password to log in and you will see slightly where is the box, click then enter your password and the windows will start then increase the brightness by using F2.

Worked for me.