In order to add the file to Avast exceptions, please follow these steps:
1. Left-click the "Avast!" icon in the system tray (a blue ball with a lower-case "a"). Choose the "Standard Shield" option.
2. Click the grey "Customize" button. Select the "Advanced" tab.
3. Locate the section titled "Here you can modify the list of locations that will not be scanned and/or tested (global exclusions are not appended)." Click the "Add" button and add the location of the virus or program you don't want avast! to raise an alarm for. Click "OK."