If the above mentioned method doesn't help, you can run an
in-place installation of Windows Vista on your computer.
To do so:
- Start Windows Vista from your hard drive and insert the Windows Vista DVD after booting.
- Run the Windows Vista setup again from within Windows Vista.
This will repair all applications including Windows Media Player and Media Center by replacing the damaged files.
It might be possible that you need to install a device driver again if you have installed the drivers for your hardware manually but normally all installed application will not be harmed by this additional installation.