You may lose some channels when you retune the TV as the channels have been rearranged. To locate them look at the EPG although you may still find that some channels are no longer available on FREEVIEW. See the following link for additional information
If the above process does not work then check the link above for additional information and also visit the accompanying site links below to find more information for your model of TV / FREEVIEW box.
For troubleshooting the retune procedure visit http://tvretune.co.uk/troubleshooting/
For specific model information visit http://tvretune.co.uk/productmanuals/
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