Malware can often leave an infected system unstable - or even unable to boot into Windows. Fortunately, a few antivirus vendors offer excellent (and free) rescue CDs that will enable you to boot, scan, and repair the infected machine. Following are the three best bootable antivirus rescue CDs available, listed in alphabetical order.
The free Avira AntiVir Rescue System combines the detection power of one of the highest rated antivirus scanners with the easiest possible means of creating a rescue CD. Simply place a writeable CD in the drive and double click the Avira rescuecd icon. If your drive is compatible, Avira will automatically create the rescue CD. If not, Avira will offer to save an .iso copy that you can burn using your favorite CD burning softare. Avira publishes a new rescuecd.exe for download several times per day. The Avira AntiVir Rescue System cannot only scan and remove malware from systems made unbootable by malware, it also provides a means for you to safely copy any data from the damaged drive.
The BitDefender Rescue Disk checks for updates while the system is booting to the CD if an active Internet connection is available. However, if an active Internet connection is not available, the update mechansim will fail. In addition to its own antivirus scanners, the BitDefender Rescue CD gets high marks for containing several useful apps, including ChkRootkit to scan for rootkits and Mozilla Firefox in the event you need to browse to a website to download additional software or get online support.
F-Secure solves the problem of keeping rescue CDs up-to-date. Boot to the F-Secure Rescue CD with an active Internet connection, and the antivirus signatures will be automatically updated and stored in memory. If you don't have an always-on Internet connection, you can download the updates to a USB drive and the F-Secure Rescue CD will access them from there. This ease-of-updating makes the free F-Secure Rescue CD one of the best available rescue solutions.