To prevent spam from being sent through your server, one of the things you need to do is keep a watchful eye on your server's mail statistics, particularly for the outgoing mail.
1) The statistics can be found in the Email category of the menu.
2) Go to View Mail Statistics.
You'll have to wait a minute for the stats to generate.
This page contains your server's mail statistics for the range of time specified below.
First on the page is an index, with a link to each section of statistics.
3) Click one of the links.
Here is the Grand total summary for the specified time period. This table lists the total volume and number of messages received, delivered, or rejected by your mail servers.
4) Scroll back up and choose a different link from the menu, or scroll through the rest of the page until you find another section that interests you.
Under Messages received per hour, you'll find a table and graph indicating the amount of mail received during the specified hours across every day in the range.
Top 50 local senders by message count shows which users on your system have been sending the most mail.
Use this section to find out the Top 50 Host destinations by message count. Our main contact address for this server is a gmail account, so this looks correct.
Many spammers or automated systems will scan all IP ranges known to belong to datacenters in hope of finding an unsecured mailserver to exploit.
You'll also see connections from legitimate users of the server who have had access to the server in the past, or current users who have simply failed to authenticate correctly.
With Top 50 rejected IPs by message count, you can find out who's been trying (and failing) to send mail through your server without permission. As you can see, even though no one has access to our server, many IPs have been trying to send mail through it.
At the bottom of the page, you'll see a List of errors split up by type and username.
You've seen a few of the sections on this page, but there are of course many more that will be useful. Check back here occasionally for any suspicious activity.
This is the end of the tutorial. You now know how to view statistics for the mail that passes through your server in WHM.