Hi All,
Looking for a little assistance. I have noticed that with my qmail install using mostly a standard configuration that if someone from a microsoft hosted account (hotmail for example) sends an email to multiple recipients on my qmail server if one of them is incorrect then none of the other recipients receive the email. I have been able to recreate this.

if I do the same thing with gmail for example, the normal delivery is experienced (all users but the incorrect address receive the email).

Any thoughts are greatly appreciated.

-Mike

My guess is the outlook.com mail servers handle recipient address errors differently from other mail server (by aborting the entire session, it would seem).

I suggest you capture the incoming SMTP transaction with tcpdump to see what's going on.