Keep the Show Desktop icon in it. If you had deleted it for some
reason, then do a search for *.scf in the drive and if you find the
Show Desktop.scf file, copy it to the Quicklaunch folder. If you do
not find it, then create a new folder.
Open Notepad and type the following:
Choose Save as from the File menu. In the dialog
box, change Save as type to All files. Give the filename as
Show Desktop.scf. Make sure you save it in the folder you
had created just then. Now, right click the taskbar and choose
Toolbar -> New Toolbar. Here choose the folder
where you had put the Show Desktop.scf file.