I don't know whether Help and Support in not available only in my computer or
in every Windows Vista operating systems. When I am not online, I can't use
Help and Support. It says, unable to download the help contents. When I
choose get offline help, the help and support becomes useless and don't work
even if connected to the Internet.

You could try this registry fix:

Pages in Windows Vista Help and Support are not displayed correctly, by
Ramesh Srinivasan:
[url]http://www.winhelponline.com/articles/194/1/[/url]

or

Error "Internet Explorer was not able to open this Internet site" when using
Help and Support in Windows Vista:
[url]http://www.winhelponline.com/articles/171/1/[/url]

"David" <David@discussions.microsoft.com> wrote in message
news:AF271962-2BB0-4D23-89B9-DCC5CCE00A75@microsoft.com...[color=blue]
>I don't know whether Help and Support in not available only in my computer
>or
> in every Windows Vista operating systems. When I am not online, I can't
> use
> Help and Support. It says, unable to download the help contents. When I
> choose get offline help, the help and support becomes useless and don't
> work
> even if connected to the Internet.[/color]