Place the script file/folder into the folder listed below.
(InCopy installations are identical to InDesign, except the desired folder is titled InCopy.)
InDesign CS3
Mac:
Hard Drive > Applications > Adobe InDesign CS3 > Scripts > Scripts Panel or
Hard Drive > Users
> [username] > Library > Preferences > Adobe InDesign >
Version 5.0 > Scripts > Scripts Panel
Windows XP:
C:Drive > Program Files > Adobe > Adobe InDesign CS3 > Scripts > Scripts Panel or
C:Drive > Documents and Settings > [username]
> Application Data > Adobe >
InDesign > Version 5.0 > Scripts > Scripts Panel
Windows Vista:
C:Drive > Program Files > Adobe > Adobe InDesign CS3 > Scripts > Scripts Panel or
C:Drive > Users > [username] > AppData > Roaming
> Adobe > InDesign > Version 5.0 > Scripts > Scripts Panel