Microsoft has announced that it will close off a component in Windows which is notorious for allowing covert malware attacks.

The company will modify the AutoPlay feature in Windows 7 to prevent external components such as USB drives automatically executing code when plugged into a PC.

The new operating system will no longer present the option to install or run programs installed on the drive, instead allowing the user to open them within Windows Explorer.

Microsoft's decision follows a string of malicious applications that exploited the component to install malware automatically.

The malware was disguised with a common name and icon option, such as 'Open folder to view files', which could then be selected by the user to run as AutoPlay, thereby launching the malware attacks.

Microsoft said that several malicious applications, including Conficker, had been exploiting the component. The attacks stem from similar techniques used by some of the earliest computer viruses to infect floppy disks.

The AutoPlay change will only apply to removable drives. Optical media, such as CDs and DVDs, will still be able to access the feature for operations such as launching game files.