Windows 7 has just been released and the big question breaks down to whether previous antivirus software designed for Windows Vista and Windows XP will work. Unfortunately, most of the legacy antivirus software, especially those with Windows services, will have some problems with Windows 7. I know this because I ran Windows 7 beta for a few months. While the antivirus software might not have been completely non functional, I ran into a lot of graphical interface problems and auto protect problems. Therefore, for those of you who have just upgraded to Windows 7, I offer a list of free antivirus that are compatible so you do have to go out to the store and buy a new copy.
1) Windows Security Essentials - I reviewed this software a few weeks ago here. Security Essentials was released especially for Windows 7 users. It's free and provides great protection. A very important feature of this antivirus is the fact that it natively supports 64bit operating systems. Very few antivirus have this functionality*
2) AVG free Edition 9.0 - This antivirus software was also just released just prior to the Windows 7 launch. It offers full compatibility with Windows 7. You can get the software here.
3) Avast Free Edition 4.8 - The features page of the software here, states that the software is compatible with Windows 7. However, 4.8 is relatively old so you might want to check out the full version. The full version comes with the "Windows 7 Certified" logo stating that software has been tested by Microsoft.
4) McAfee Beta Total Protection for Windows 7 - this is a new antivirus program offered by McAfee. The software is free but it is in beta so it still may have some bugs. Get it here.
5) McAfee Internet Security - I saw this the other day when I was logging in. McAfee is offering 12 free months of security for Bank of America online users. Get it here
Finally, most antivirus vendors have made sure their products are compatible with the latest verison of Windows. The thing that consumers need to look for are the "Certified for Windows 7" logos. This will ensure that the software is completely compatible with Windows 7. Good Luck with making your version of Windows 7 more secure from viruses!