See the links to the right for usage/install instructions for your anti-virus client.
For Campus Owned Computers
New Windows computers are deployed with F-Secure AntiVirus software.
New Macintosh computers are deployed with Sophos AntiVirus software.
For at Home
Avast (Windows): Avast! is a CTS User Services favorite for our home computers. The free version for home use is all you need: http://www.avast.com/eng/avast_4_home.html
Sophos (Mac OS X): There is a free "Sophos AntiVirus for Mac Home Edition" available at: http://www.sophos.com/products/free-tools/free-mac-anti-virus/