Microsoft Windows includes an AutoRun feature, which can automatically run code when removable devices are connected to the computer.
Disable AutoRun In Windows Vista
- Click Start
Collapse this imageExpand this image,type Gpedit.msc in the Start Search box, and then press ENTER. Collapse this imageExpand this image 
If you are prompted for an administrator password or for a confirmation, type the password, or click Allow. - Under Computer Configuration, expand Administrative Templates, expand Windows Components, and then click Autoplay Policies.
- In the Details pane, double-click Turn off Autoplay.
- Click Enabled, and then select All drives in the Turn off Autoplay on box to disable Autorun on all drives.
- Restart the computer.
Windows Server 2003, Windows XP, and Windows 2000
- Click Start, click Run, type Gpedit.msc in the Open box, and then click OK.
- Under Computer Configuration, expand Administrative Templates, and then click System.
- In the Settings pane, right-click Turn off Autoplay, and then click Properties.
Note In Windows 2000, the policy setting is named Disable Autoplay. - Click Enabled, and then select All drives in the Turn off Autoplay box to disable Autorun on all drives.
- Click OK to close the Turn off Autoplay Properties dialog box.
- Restart the computer.
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