To clear addresses all at once, you simply need to select them all before clicking 'Forget'. The selection can be done in a few ways:
- Hold Ctrl and select the lines with with the mouse; or
- Hold Shift and click with the mouse on the first and then the last line to be selected; or
- Hold Shift and use the Up and Down keyboard keys; or
- Press Ctrl + A to select everything.
These keyboard shortcuts are applicable to most Windows applications.