Menu items not visible, not open or strange behaviour

Errors and Error Messages
If you find that menus or other objects are not behaving properly, or missing, it's likely that your firewall is blocking javascript from running.  
To solve this, find where you can add exclusions to your software and be sure to include the url you use to login to EP as a site to exclude from the firewall.

It also can be related to the enabled "Internet Explorer Enhanced Security Configuration (ESC)" in Windows, so disable it in Server Manager.
It's also recommended to add your EP site to Trusted Sites zone in your IE settings. Please refer to

Note that the Compatibility View mode in Internet Explorer is not supported, it should be disabled in order for Easy Projects UI to be displayed correctly.