Can't click on Desktop Icons OR Can't run applications from Desktop Icons.

Problem: Can't click on Desktop Icons OR Can't run applications by clicking Desktop Icons.

Solution: Kill the process "explorer.exe" from Task manager (press CTRL+ALT+DEL and select Task Manager and go to Processes Tab). Create the same task by switching to "Applications" Tab, click "New Task" and type "explorer.exe" in that and then OK. Your problem is solved!