This can be due to any anti spyware in your system which has affected your Windows registry. Editing your Windows registry will fix the issue out. Do this click on Orb and in the search box type regedit. Then navigate to the following path - [HKEY_CURRENT_USER\Software\Microsoft\Wi… ntVersion\Policies\Explorer]. Here check for
NoViewContextMenu and see that you can see REG_DWORD value. Right click on it choose modify and set the value to 1. If it set to 0 then it is disable. Restart your system and check out.
