Smart Slider 3's menu is missing

If you're running 3.3.12 or below, update, because this solution is available from version 3.3.13.

This problem usually happens, when something goes wrong during Smart Slider 3's installation and some codes are not running properly.

How to fix the problem?

Go to WordPress > Plugins  and find Smart Slider 3 in your plugin list. Then click on Repair, which should fix the problem.