Why can't I take screenshots on my Android devices?

[futurefields]

I have a Samsung Galaxy Tab Pro 8.4 and a Samsung Galaxy S6 Edge Plus.

Every guide I read says you hold the home button and the power button, and you will get a screenshot, but this isn't happening for either of my devices.

 

[blackangst1]

Are you holding them down long enough?

 

[futurefields]

I figured it out, thanks.