This problem is not a common problem but when it occurs it becomes very irritating… so if ever it has happened then what to do? Get through the below steps to solve this problem.

To enable this option you need to open gpedit.msc which handles this menu but since the run menu is missing you will have to open it through administrative tools from the conrtol panel.

Now  Go to user configuration ->  admin templates -> click “Start Menu and Taskbar”. Look for the option “remove run menu from start menu” on the right side. Double click it and ensure that it is Enabled.

Hope this would have solved your problem… enjoy