Symptoms

Some or all of the overlay icons don't appear in Windows Explorer - such as:
Pinned, currently pinning, uploading, etc.

Solution

1. Open the Registry Editor and navigate to: Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\
   ShellIconOverlayIdentifiers

2. A screen similar to this will greet you:
   

3. Rename the keys under ShellIconOverlayIdentifiers that are not Lucid related, so that they don’t have the spaces before them (the aim is that the Lucid keys are first in the list).
   
4. The end result should look something like this once you refresh the screen (F5):
   
   
5. Open Command Prompt;
6. Run the following command: taskkill /f /im explorer.exe
   Note: Your Taskbar and Desktop will disappear until you run the next command.
7. Run the following command: start explorer.exe

Please note that you might need to restart your computer if the commands from step 6 and 7 don't solve the issue.

Cause

By default, Windows allows a maximum of 11 custom icon overlay handlers to be active, other software might have those places reserved for themselves.