Thanks for your post and apologies to hear you are having an issue registering your iPad.
As iPad's dont have Flash Player, you'll need to register the device within the app.
Download the TV Anywhere app and once you have logged in, select Channel 4 and try to stream. You will then be prompted to register the device. Follow those prompts and you shouldn't have any further issues
Let me know how things go.
Kath_F Forum Team
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