Quick Launch icons generic – not app

I’ve added two shortcuts to many users Quick Launch bars. These shortcuts are functional, but after a system logon, the displayed icon is generic – not the icon for the underlying app. Right clicking the QL bar and ‘refreshing’ results in the propericons. The shortcut points to an app on a shared network drive. I don’t have the same problem on my PC however – even though my config is the same. Why might they not be working for users? Is it because our drive mapping may not be complete when theQL bar is started? Is there a way to automate a refresh of the QL bar?