Freeview Retune on PC

[evolution400]

Hi guys anyone done a re-tune on a PC using Windows Media Center ?
I am running W7 MC and I seam to have lost Sky three, E4 +1, Yesterday, Sky News, Sky Sports news etc probably more just wondering if this is a PC issue or Transmitter I am in South Wales so using Wenvoe.
Thanks.

 

[evolution400]

all working now it appears to have been transmitter issue