Microsoft didn't make it easy to change the tile color on
your Windows 8.1 machine. There is no easy way to do it in
You can personalize the theme colors. Right click on your
desktop and select "Personalize". You can choose your own
"Accent Color". Don't let Windows pick for you. You can also
personalize your task bar by rigth clicking on that.
The Windows Club offers a Tile Color Changer, but that is a download app.