I'm assuming you mean the 4 app for channel 4 etc.
It should be one of the standard apps alongside iPlayer, ITVX and 5.
Is you box connected to an external aerial? If not this and ITVX probably won't show as it needs an aerial connection to confirm your region. You could set this up maybe on a friendly neighbours aerial and then move back to your home.
If you have a working aerial and the app does not show, then you will need to reset your box to factory settings (from the settings menu) and the app should be installed.
Let us know how you get on.
Please remember to mark Solved Posts with Best Answer. Doing so helps other customers and saves TalkTalk's Support Team time by only looking at unsolved topics. Thanks, Steve (a fellow customer).
