Does windows 7 have a tv tuner or drivers

Have a check in control panel, then click on hardware and sound Icon.
Once in there click on device manager have a look in the list under sound and video devices. The drivers should be listed as installed to use your Tv card, if not simply they are not installed windows media center will not work if they are not installed, the drivers for the card are not installed more than likely you forgot to install them. A factory restore does not always pre install third party drivers for devices you have to manually install them yourself after a factory restore. There should be a folder on a partition on the Hd with all the drivers for the hardware in the system though so have a look around.

+1 to weaselman

are you using media center not media player?