Yesterday, a new member joined my listserv(MEDLAB-L) and successfully posted to it.Today a message that I posted to MEDLAB-L reports an error for his address(see below).Can anyone help me fix the problem? Thanks, Pat ______________________________________________________ From: [log in to unmask] Subject: Returned mail: Service unavailable Subject: to To: <@VM.UCS.UALBERTA.CA:[log in to unmask]> Content-Length: 0 ----- Transcript of session follows ----- Connected to condor: >>> HELO dns.unam.mx <<< 553 dns.unam.mx host name configuration error 554 <[log in to unmask]>... Service unavailable ******************************************* "Round up the usual suspects." -Captain Louis Renault ******************************************* Pat Letendre Medical Laboratory Science B117 Clinical Sciences Bldg University of Alberta Edmonton,Alberta Canada T6G 2G3 Phone:(403)492-6507 Fax:(403)492-7794 E-mail:[log in to unmask] *******************************************