At first you have to go start menu button and click on Run or  keyboard shortcut key(start button + r  ) and write down hole box gpedit.msc and click on OK and you will see Group Policy Object  and go to User configuration and click Administrative template and click on Windows components  click on Windows Explorer and click on Hide these specified dive in My Computer and click as mark  Enabled   and go to My computer and see all drive are hidden and you will restore this and you have to again this work carefully and change just Enable to  Not Configured ...and  see image below.....