All,
Sorry for the crosspost, but either list could bring thoughts to this, and the Exchange list hasn't been responsive today - I'm not getting anywhere near the volume there that I normally do. I have set up and piloted a relay server using Win2k and its SMTP service. The box is up-to-date, fully SPed, etc. I pointed my firewall away from the linux/sendmail box that was serving as the outside point of contact for our email, and towards the Win2k box. I've notice several things: We have about 300 Exchange 5.5 mailboxes here. Over the weekend that I had this turned up, we got more than 900 NDRs, and a huge amount of spam. The spam I'm not too worried about (although if you have worked with an anti-spam utility on a Win2k relay box I'd love to hear about it), nor am I worried about the unusually high amount of mail to ex-employees. What I am worried about is the amazing number of NDRs that contain the following message: Action: failed Status: 5.6.1 Diagnostic-Code: smtp;554 5.6.1 Body type not supported by Remote Host I've done a google on the last line of the NDR message, and all I found was a message from August of last year with someone else having the same problem, and no replies. He describes the problem quite nicely, too. (see http://archives.neohapsis.com/archives/firewalls/2001-q3/1025.html) I have to wonder if this problem isn't related to another issue I'm having using this box to do relay to external hosts - it works fine for most relaying, but has real problems talking with attbi.com, microsoft.com, msn.com, and a friend's Exchange2K box that I've been testing against. Does anyone have thoughts on this? Many thanks for your help, Kurt List Charter and FAQ at: http://www.sunbelt-software.com/exchange_list_charter.htm
