Just so you all know, I got my information directly from one of the engineers at Yahoo! Groups. Your scenario sounds pretty promising. I've got a slightly different theory. It's not that Y! Groups is triggering a spam response in my scenario, but simply that the huge amount of mail is just overwhelming some ISP's mailservers. Fuzzy -- Quidquid Latine dictum sit, altum videtur. Si hoc legere scis, nimium eruditionis habes. Vir sapit qui pauca loquitur. Cras amet qui numquam amavit, quique amavit cras plus amet. Uno itinere non potest perveniri ad tam grande secretum. On Sat, 27 Sep 2003, Spider wrote: > Here's my take on what is going on. Since no one has access to really good > information about the inner workings of Yahoo Groups and how the many > different ISP's handle their mail we can only guess. > >>> SNIP <<< > > Considering that Yahoo Groups is large, and during a busy period might > send out lots of email, I think they are triggering a SPAM response with > some of the ISP's. The ISP may respond to the perceived SPAM attack by > automaticly bouncing the message with an "unknown recipient" message. > The intent is that the spammer will then drop that email address from > their list and reduce the spam. Some ISP's then trigger a block of that > domain. This can remain blocked until someone at the ISP manually > releases the block, or they might configure to block for a period of > time. > > This is only one of many scenarios that could cause this type of issue. > There is not an easy solution to this problem. > > Spider For a web-based membership management utility and information on list policies, please see http://nibec.com/24hoursupport/ To unsubscribe, send a blank email to 24hoursupport-request@xxxxxxxxxxxxx with "unsubscribe" (without quotes) in the subject.