On Wed, Jul 8, 2009 at 3:26 PM, Wulff Jr, Ronald J.<rwu...@reedsmith.com> wrote: > Yeah, that makes sense, I'm just not sure why Postini just started acting up > with > these messages, but who really knows what goes one there
Assuming it's not a recent configuration change done by the receiving system's mail admins (as James Knoch describes), Postini may just have changed their spam heuristics recently, to do the sort of "Does this look like a DSN?" analysis I supposed. Note that SMTP DSNs (Delivery Status Notifications) include delivery failure, delivery delay, and return receipt. "NDR" is an Exchange term that applies equally well to a subset of DSNs. -- Ben
