you may have no connection to the network. Have you got a flashing green light on the front of the box? It's worth checking the VM website to see if there's a problem with catch up in your area. If so it'll give you an estimated fix date.
also it's always worth trying a reboot (off then on) of the box as this will sometimes fix odd things.
I'm sorry to hear that you're getting an error when using On Demand. I'll be happy to help check this out for you.
I have connected to your box remotely and all looks great signal and power level wise. If the fault still present today? If it is, if you can tell me more about the error message and if it quotes a code at the end that would help me greatly in pin pointing the fault.
I'm here if you need me, keep me posted
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