I'm running a dedicated server with hostgator and it has Spamassassin running, which isn't really blocking anything at all. I really need to stop the spam, my users keep opening virus attachments and getting heaps of spam messages. I'd like something I can just install in whm or cpanel and have it automated, at the moment I'm running a bunch of RBLs with SA and custom rules then having ClamAV scans each day. Can anyone suggest a solution? I'd rather a free one but at this point happy to pay
I'm assuming you have other typically helpful settings enabled in cPanel/WHM such as Sender Verification or Sender Verification Callouts? Have you adjusted the SpamAssassin rules at all, or have it set globally? Is it only a few users experiencing the problem? I guess it depends how severe the issue is, and how much you're willing to spend for a paid solution. You could pay for a monthly service which does spam-filtering, or buy a hardware based solution and colocate it with your provider (if possible, they may even have a solution they can offer you).
I recommend SpamExperts. They operate a great service. For a great outgoing smarthost service, try SMTPCorp.com. Otherwise, you mentioned RBLs but not sure which ones you are using: Login to WHM, go to Exim Configuration Manager and click on the RBLs tab. Enable Spamcop and Spamhaus but also add the two custom ones shown below. When done, your list will look like this: Origin RBLname DNS list Info URL Custom abuseeat cbl.abuseat.org http://cbl.abuseat.org Custom barracuda b.barracudacentral.org http://barracudacentral.org
Have you adjusted the rules or settings at all? By default, SpamAssassin isn't terribly great, but it can really be customized.
Make sure in WHM you have enabled blacklisting in the Exim configuration. I recommend no more than 3 blacklists. b.barracudacentral.org zen.spamhaus.org bl.spamcop.net These 3 tend to produce good results and use slightly different mechanisms. http://docs.cpanel.net/twiki/bin/view/AllDocumentation/WHMDocs/ManageRbls
Along with SpamAssasin you should consider SpamExperts. You can also Install Maldet, and setup ConfigServer exploit Scanner (CXS) on your server. These things will help you to improve server security. Ask HG support to configure these 3 things on your server.
You can try Vade Retro for CPANEL (https://www.vade-retro.com/en/products/cpanel-plugin.asp). You get 1 month for free and then, the pricing is very very competitive; 1$ / domain / month. It provides "Gmail like" features to your email environment by implementing dedicated folders for marketing emails, newsletters, social media emails with an unsubscribe features for those low priority emails. Vade Retro is very well known in the antispam market as it is currently protecting 235 Millions of mailboxes with partnership like OVH, Cisco or Orange Telecom.
I see that this rather old thread got some traction again. I would also suggest looking into SpamExperts, especially if you would be looking to protect your customers "in bulk", sort of a value-add service in the hosting package. You can also ask HostGator about SpamExperts, as far as I know, HG is using them already.