How to restore the display desktop button in the Win7 taskbar

In general, we are accustomed to directly click the "Show desktop" button in the quick launch bar of the taskbar to minimize all windows, especially open. Minimizing all open windows in a lot of windows is even more annoying. However, this "display desktop" button is often disappeared. In addition to pressing the shortcut key Windows
+D to minimize the key, how do we restore this display desktop button?

Operation steps

1, first open Windows7 and start running dialog box. (can be opened by pressing Win+R shortcut)

2, then enter the :regsvr32 /n /i:u shell32 command in the Open “Run” command dialog box, enter Click the “OK” button once you're done.

3. After entering the command and clicking on the button to confirm the ” button, the dialog box that DlllInstall has successfully prompted in shelll32 will pop up.

3, after we click OK, we can see that the “Show Desktop” button is back in the taskbar of windows7.