Youtube app not working on iPad - immediately closes when try to open (worked previously)

Quit YouTube and restart.

Go to the home screen first by tapping the home button. Quit/close open apps by double tapping the home button and the task bar will appear with all of you recent/open apps displayed at the bottom. Tap and hold down on any app icon until it begins to wiggle. Tap the minus ➖ sign in the upper left corner to close the apps. Restart the iPad. Restart the iPad by holding down on the sleep button until the red slider appears and then slide to shut off. To power up hold the sleep button until the Apple logo appears and let go of the button.

Or try a reset.

Reset the iPad by holding down on the sleep and home buttons at the same time for about 10-15 seconds until the Apple Logo appears - ignore the red slider - let go of the buttons.

First close the App fully: double tap home button to bring up taks bar (most recently used apps). next, hold finger on any of the apps until they jiggle and you see a minus sign in the upper left hand corner. touch the minus sign on YouTube app (heck, close all the apps while your'e at it). tap home button to return to home page.

Next: reboot your iPad: press and hold BOTH the power and home buttons at the SAME time for about 10 seconds (ignore the red slider to shut down) until the Apple Logo appears, then let go of both buttons and your iPad will restart.

Try the YouTube again and see if you can watch videos.

Resetting will not cause a loss of data.

Apps and settings are Both considered data.

The reset that I am describing or the reboot that rbrylaswki is describing are the same thing. If you reset/reboot your iPad you will not lose any apps, data, content - nothing at all. The procedure is very similar to rebooting your computer.