Comodo offers a wide range of full-featured desktop security products totally free of any charges with free updates for lifetime, as well as commercial products for server systems.
Free Desktop PC Security - Free Downloads Keep your PC Safe | Comodo
Firewall & AntiVirus Software Suite - Internet Security | Comodo
Windows XP (SP2) or Vista 32 bit or Windows 7.0 32 bit
64 MB RAM / 70 MB hard disk space
Windows XP (SP2) or Vista 64 bit or Windows 7.0 64 bit
64 MB RAM / 105 MB hard disk space
Please note that the freeware products are not fully compatible with Server operating systems.