click here for the virus bulletin tests for June 2003 using Windows XP. Both Alwils Avast4 & Grisofts AVG 6.0 get the 100% in this test, but Avast has the better track record in previous tests. The upcoming AVG 7.0 has yet to be tested. Because of the freeware license terms, one copy only free, I use both, The more expensive laptop uses avast and the desktop has AVG. Personally I rate avast 4 as the better of them. As with AVG the free version has scheduling limitations, but it can be set to scan in screensaver and the update is fully automatic . There is only one other free Windows antivirus prog that I know of and that's Antivir click here , it's OK, but the scan is slow and update files are on the large size, so I would put it third on the list.