What to do when the YouTube app is no longer functional?

The YouTube app was incorrectly installed or needs to be updated to a newer app version.
Since Google has deprecated the API v2 in April 2015, the old pre-installed Youtube app is no longer supported. YouTube currently has two apps available for Android TVs. The “YouTube for Google TV” (for 2014 Android TVs) and the “YouTube for Android TV” (for 2015 Android TVs).

To continue to use YouTube via the TV, the new YouTube app from the Google Play store should be installed as follows:

If the “YouTube for Google TV” app is currently installed, uninstall it from the TV.
The currently installed app can be found via the Google Play store:
● Select the button on the left of the Google play search field and press [OK] on the remote to open the Google Play menu

● Choose the [My apps] option to view the list of installed apps

● Choose the currently installed YouTube app from the list
● Select the “Uninstall” option and press [OK] on the remote control

Then, the Google TV app can be installed as follows:

● Open the Google Play store on the TV
● Search for the app “YouTube for Android TV”

Note: If the pre-installed YouTube app has been manually disabled, the app needs to be re-enabled first. To do this, choose the green “Enable” button and press “OK” on the remote control. Afterwards proceed with the steps below.

● Select the white [Update] button and wait until the app has updated

● If the update was successful, the former pre-installed icon will be changed into the new icon

• Switch the TV OFF
• Unplug the power cable of the TV
• Wait for one minute (after the LED light has switched off) before the power cable is plugged in
• Switch the TV back ON