Mail problem

For every message I send to the tuning list, I get this reply from
support@x-networks.net. Could someone please fix this?

There is no one here by the username of "mnt99"

Please double check your contact list.

[Herman Miller:]
> For every message I send to the tuning list, I get this reply from
> support@x-networks.net. Could someone please fix this?
>
> There is no one here by the username of "mnt99"
>
> Please double check your contact list.

Same here, and worse yet some go through and others disappear (or show
up several hours later).

Dan