The most common way of malware infection these days is through infected USB keys. The infected USB keys have a malicious autorun.inf file on it that is specially written to run the malware as soon as you insert the key to a USB port on your PC. Once your PC is infected, it keeps infecting the new USB keys that you plug into your computer. There are many tools for protection against this type of malware. Antirun is one of such tools that can protect your PC against autorun virus and remove the malicious autorun.inf files upon detection.
You can download the Antirun utility from the Antirun website. The download is a setup installer file of about three megabytes which can install Antirun on your PC. After the installation, Antirun icon would be placed in the notification area (system tray) of your Windows desktop. It keeps monitoring for newly added USB keys and removable disks. As soon as you plug in a new USB key, it checks it for autorun malware and disinfects if it is found.
There is an immunization feature but it works only in the Pro edition for which you have to pay. The immunization feature is similar to the vaccination feature in the Panda USB Vaccine utility. It places an undeletable autorun.inf file on the USB keys so that it cannot be overwritten or modified by any virus. This way your USB keys stay uninfected even when they are used on an infected system.
In the settings for AntiRun, you can choose to run AntuRun at Windows startup, disable AutoRun for all the devices, choose not to be bothered by the informational dialogs if the autorun.inf file is not found on the inserted device and so on.
AntiRun provides with great features to fight against the autorun.inf virus like disabling autorun on your computer, automatically remove malicious autorun.inf files etc. But it does not give access to the immunize function in the freeware edition. For this feature, you can get the Pro version which has some other extra features as well.
You can download AntiRun from http://antirun.net/.