OS = Operating System. Win7, in your case.
What happens when you try to open a wmv file?
You can turn features on or off in  Control Pane/Programs and
Features/Windows Features/Media Features. It's unlikely that's what
you did, however.
There are many programs that will play wmv files including Windows
Media Player and VLC.
http://www.videolan.org/vlc/

On Sun, Apr 8, 2012 at 6:58 AM, awillett <[log in to unmask]> wrote:
> -----Original Message----- From: Hugh Vandervoort
> Sent: Saturday, April 07, 2012 10:26 PM
> To: [log in to unmask]
> Subject: Re: [PCSOFT] Windows media center
>
>
> Interesting question, but not clear. You have to have an OS, so what
> exactly are you trying to do?
>
> Sorry, I don't know what an OS is. My computer is fairly new, less than a
> year old and came with Windows 7. I think I may have deleted something that
> I shouldn't have and I cannot open wvm files. I would like to reinstall the
> Media Center.

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