Sky Plus

[Eve]

Everytime I turn the box on it comes up that a satellite signal cannot be found. If you switch it off then wait and switch it back on again and wait again it comes back on.

Is it likely to be a problem with the box or satellite or set up and is there an easy way to fix it for good?

We are connected to a communal dish as live in a block of flats.

Thank you for any advice :)