Windows 7 media centre suddenly wont work

hi all,ive been having big problems with media centre for the last 4 days,,been using it for over 12 months without any problems,,then suddenly started to lose signal on and off,just thought it was a blip,so didnt worry,but then it went off completely,im using a USB freeview dongle,like i say,has worked great for 12 months,,,so,,,i have bought another dongle,plugged into different USB ports and it is recognised in device manager(REALTEK 2832U device) and 1 of the lights is lit on the dongle,but when i try to go through the WMC tv setup,it is unable to find a signal,,it knows the tuner is there,as it asks me if i want to set up the DVB-T tuner manually,ive even reinstalled W7 yesterday,but still it will not work,,the signal is there,as i have tested it on a freeview box on my tv and it was fine.
I'm stumped as to why it has suddenly done this ,im giving myself headache trying to work this out,if anyone has any ideas they could give me,i would be soooo grateful,,seriously,i will buy you a pint if i ever see you,i miss my WMC so much.

Any more details that aren't on profile please just ask,,im not too bad at following instructions if i need to change anything,,but please,,HELPPPPP...thank's for reading my woes...Daz.

p.s...blazedtv software doesnt find anything either,,so it is working,but nothing is picking up a signal

mark as solved...or delete.