I am trying to download an application, but it will not download because it says DashboardClient is open. I just want to find it and close it.
Dashboard is essentially a pared-down web browser. Adobe Flash installers usually look for open web browsers before installing and recommend they be shut down prior to install. So, try going into Dashboard and then move your mouse over any open widgets and then hold the option (or alt) key down and a small (x) should appear on the top left hand corner of the widget. Click that to close the widget. Repeat that for all the open widgets and then retry the Flash installer.