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The first way I tried was just to type in the code, using the number buttons on the remote keypad, but this didn't work, so, seeing as there's a keypad on screen, and with a little lateral thinking I found that the arrow keys on the remote move the coloured square on the keypad, highlight each numer, enter it and then move to the enter key on the keypad, lo and behold, the nest episode. Hope it works for you. Maybe they are testing for real spooks :)