This dialog is used to select a destination directory to either copy or move Scripts.
Q++ allows you to place your scripts in any sub-directory of c:\qpp\scripts on your PC or any other user's PC. However, whenever an update to Q++ is applied, the updating of the Scripts is done on each PC as each user logs on and updates the Q++ setup on his/her PC. This means that if you placed some scripts on another user's PC and you try to access these when he/she is away and has not updated Q++ on his PC, you will not be able to access these scripts and will have to wait until your colleague returns.
For more details, see the Scripts Explorer.