How can I block email to coming to my IP in exchange 2003

in ESM find your server and expand it -> Protocols -> SMTP -> Default SMTP virutal server right click properties -> go to the access tab -> in the connection control click on connections and set it to access only from the IPs you want

Let's look at this from a different angle -

While it's best practices to allow mail only from your Postini IP, we need to address why you are getting mails to your Exchange IP in the first place which is the bigger problem.

If these are just spam mails and not mails that you care to receive, then ignore all of this.

If you are getting legit non-spam mails sent directly to your Exchange server, then it still exists as an MX record for your domain.

Goto mxtoolbox.com and put your domain into the search box, and then see if any of the MX records are pointing to you.  If you are using Postini as a filter between the internet and your mail server, then there should only be Postini MX records (domain is psmtp.com).

We use the firewall on our Draytek router to block any SMTP traffic to the network except from our mail scanning service. This reduces any possible attack surface and should be possible with most firewalls.

Parpertrip is correct to suggest looking at your MX records but I have found that the servers spam tends to originate from will send to any address in its database, regardless of whether it is a current MX, specifically for this reason.

Thanks

Gareth

Hi, is this still an issue?

it's a B because it doesn't take into account for Alias emails That are not paid for under Postini