To remove all unwanted or potentially harmful items that Microsoft Security Essentials detects quickly and easily, use the Clean computer option.

  1. When you see the notification message that Security Essentials displays in the Notification area after it detects potential threats, click Clean computer.

  2. Security Essentials removes the potential threat (or threats), and then notifies you when it's finished cleaning your computer.

  3. To learn more about the detected threats, click the History tab, and then select All detected items.

  4. If you don't see all the detected items, click View details. If you're prompted for an administrator password or confirmation, type the password or confirm the action. On systems running Windows XP, you may need to log on as an administrator on this computer.

Note:
During computer cleanup, whenever possible, Security Essentials removes only the infected part of a file, not the entire file.