Listmaster. was: Why did I get this message after posting to this forum?

I also got the same message

Donald Brock wrote:

> You have attempted to send email to an invalid user at the
> adelphia.com
> domain. Currently this domain is not used for email. If you are
> trying
> to reach the email address of an Adelphia powerlink subscriber,
> please
> send your email to them at adelphia.net.
>
> For more information, please see Adelphia Powerlink's home page at
> http://powerlink.adelphia.net
>
> ---------------------------
>
> I received this message via e-mail after posting to this group.
> Can some one tell me why?
>
> Donald Brock
>