It turns out that the problems I was experiencing were down to the communal aerial's amplifier not working properly. It has now been replaced by an engineer and everything is working properly. The engineer mentioned that a lot of people in the area have been having problems following the storms at the weekend.
Thank you to everyone who responded. New technology is great until it stops working and then I realise how little I actually understand about it!
Anyone else lost their Freeview signal for the last two hours.( tuespm 7.15ish pm onwards)
I have tried everything, re booting, scanning for channels and good old turnong on and off.
The aerial is attached firmely?