If accidentally your ‘Show Desktop’ icon is deleted from quick lunch toolbar then do the following step
1. Open new notepad
2. Paste the following code in the notepad
3.Go to file menu and select Save As and in the file name write name as “Show Desktop.scf” and save it on desktop (you can save anywhere you want). Make sure that ‘Save as file’ should have all files selected.
4.Drag & drop the file to the quick lunch bar .. and you are DONE!!
-Ravi Kumar V.