Not getting a preview to the window I'm hovering over with my mouse (taskbar)

[Wilson_2]

Whenever I hover over a window on my taskbar it doesn't show a preview to the window and instead it shows the file name. (Yes I know task manager isn't an active window but it's just an example.)

https://gyazo.com/98f2dcf0cf38ce24e9d3f3d2b85dc4bc

 

[woodson75]

I guess you want to do the reverse of this: http://superuser.com/questions/755553/how-to-disable-taskbar-thumbnail-preview-in-windows-8