Try https://support.msn.com/eform.aspx?productKey=edfsmsbl&ct=eformts Is it hotmail users sending your users emails that are being rejected, or is it your users sending hotmail emails that end up rejected? /r From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu] On Behalf Of Jason J. W. Williams Sent: Wednesday, April 02, 2008 5:31 PM To: nanog@merit.edu Subject: Hotmail NOC Contact Hey All, Does anyone have a good contact number for the Hotmail NOC? We've got e-mails from Hotmail to some of our customers being returned the Hotmail sender with a 554 error message fairly regularly. Our logs aren't showing any rejections, so we need to talk to Hotmail and find out what the 554 means on their side (there's no error description). Any help is greatly appreciated. -J ________________________ Jason J. W. Williams COO/CTO, DigiTar http://www.digitar.com Voice: 208.343.8520 Mobile: 208.863.0727 FAX: 208.322-8522 E-mail: williamsjj@digitar.com XMPP/Jabber: williamsjj@digitar.com