Two options:
1) Activate the the clear Net TV Memory function.
- This can be found by pressing the options button on the remote control, which is just above the volume button, and accessing the menu (Note: After this you must accept the terms of use and register again at Club Philips).
- Confirm your email and password on YouTube to make sure you are putting the right one in
2) Sign in with your Google account rather than the old YouTube user name.