There are two reasons why your will get the "This is the wrong card for this set top box" on your Sky box.

The first reason is that you are trying to watch Sky Sports or Sky Movies on a Sky digibox that the card is not paired to. Although you can use a Sky viewing card in any Sky box and still watch any of the "6 mix" channels, for Sky Sports and Sky Movie channels, the card has to be paired to the box. This can only be done by calling Sky.

The second reason is that your sky viewing card has not been receiving its activation signals and has "gone to sleep". It will "go into hibernation" if the card does not receive a signal after a few weeks, which is why many holiday makers come back to their Sky TV and see this message, as they may have switched off all the power to the Sky box whilst they were away. To wake up the card, make sure your Sky box is turned on and receiving signal, make sure the card is inserted correctly, and wait. It can take up to 72 hours for the card to wake up. Failing that, contact Sky to resend an activation signal through.