1. For the solution first of all press "CTRL+SHIFT+ESE" from your keyboard at once.
२. After that "Windows Task-bar manger box will appear" from top of this window click on "File" and then click on "New Task-bar Run..
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3. Now at "Creat New Task" type Explorer.exe and press OK.
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After that the Windows Explorer will open and all your existing programs will automatically appears and your taskbar and all icon will also appear as before.