I don't think contacting anybody at Yahoo will help. The best way I think is to use another mailserver in front of Exchange that is more efficient in sending the emails to yahoo.com One of possibility is to use Postfix. Postfix supports SMTP Connection Cache http://www.postfix.org/CONNECTION_CACHE_README.html which will allow it to send multiple email messages to the same destination using one SMTP session. So, if your email server needs to send two different emails to a@xxxxxxxxx, and b@xxxxxxxxx (eg: A's loan is accepted, while B's load is denied), then with SMTP Connection Cache, Postfix will just open a connection, and send email to A and B together within the same connection. This is different with IIS SMTP server in the sense, it only able to group emails within a connection if the emails are generated at the same time (thus having the same message id), eg: at your outlook, you type at the To: a@xxxxxxxxx, b@xxxxxxxxx, c@xxxxxxxxx (kind of emails from mailing list server). Of course the drawback is just Postfix only run on a *nix based box. On 1/23/06, Evan Mann <emann@xxxxxxxxxxxxxxxxxxxxx> wrote: > http://www.MSExchange.org/ > > > Does anyone have any particular contact info for Yahoo Postmasters? I've > been getting heavy delays over the past 3-4 weeks. It appears that they are > limiting my number of active connections per hour. I found some random for > by searching Google Groups and submited, but I'm not very confident in any > action will be taking. My company generates A LOT of mail to yahoo accounts > (none spam), but I think they've flagged us as some level of spammer.