Help! Is it me or the other machine?

I am a wrestling coach and tried to send a message to our state bulletin board moderator. I use OE 6 and Hotmail. I got this message back.



The original message was received at Mon, 25 Oct 2004 18:55:20 -0400
from bay22-f26.bay22.hotmail.com [64.4.16.76]

----- The following addresses had permanent fatal errors -----
<wrestle@wvmat.com>
(reason: 553 5.3.0 <tmiller@mountain.net>... DENY This machine is being used as a spam relay please call 304-848-5422.)

----- Transcript of session follows -----
... while talking to rx.citynet.net.:
>>> RCPT To:<tmiller@mountain.net>
<<< 553 5.3.0 <tmiller@mountain.net>... DENY This machine is being used as a spam relay please call 304-848-5422.
550 5.1.1 <wrestle@wvmat.com>... User unknown


Is it my machine or the other one and if it's mine how can I clean it up? I ran AdAware and Spybot and they didn't find anything.

Thanks to all....
Jim