While it's possible that some here might have knowledge about how to protect a website from attack, most of the forum security participants focus on how end-users can protect their personal PC... and I see these as being very different.   Assuming you're talking about hosting on a live server, that will be active 24/7, you're talking about maintaining continuous security there, even when your personal PC is off, and you're not around to monitor what's happening online. Will your site be generating any revenue?   If so, be advised that most of the free anti-virus programs will not be legally usable... they're typically free only for personal, home, non-commercial use.   And even if you don't generate any revenue there, you'll need to carefully check out any other applicable legal restrictions.
 I'm ready to launch my website to the world and I'm looking for advice on an excellent antivirus program for free or even a yearly fee.  I have a Dell PC and using Windows 7. I built my own social network website from scratch with Dreamweaver CS4.  Any information and suggestions will greatly be appreciated.   　  Thank you,    Scott 
Looking for a ANTIVIRUS Program that will protect my website.