My sky box doesn't pick up any channels, Help?

-Hi

Recently my sky box upstairs has stopped working. It occasionally picks up random channels but usually says that it cannot pick up a sattellite connection or cannot connect. The weather has been fine over here, really hot infact. It is a multiroom tv that is now out of contract for two years, though it still would work. There is only one sky dish but it connects the two boxes. Could it be the viewing card, the upstairs connection or then the box itself? Thanks in advance for any help, and asap please :)Apart from doing as already advised, you could try the upstairs box on the other connection. If it works OK, then you know that it is not the problem. Could be a cable or connection problem, or interference of some kind.

http://www.satcure.co.uk/digirep.htm