Hi and welcome,
I have heard rumours that Sky had "upped" its encryption on HD and Premium Sports and movie channels, as part of its anti-piracy measures.
And one of these measures is to try and stop its card being used in other "non sky" receivers - a sort of "hard pairing" of card between boxes. Maybe something to do with the new "receiver ID" on the sky box system details, or a "trick up their sleeve" prior to any sky card change that is rumoured next year..
Perhaps you need to load the latest software into your receiver? (new software for the 120combo was release in April - ferguson-digital.eu/en/download/HD-Satellite-Receivers/ariva-120-combo)
If that does not work, then another receiver that it does still work on.
I have not an Ariva on me at the moment so I cannot test.
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