There are times we may encounter a situation in which we want to reinstall Prepar3D again due to some annoying issues caused by unknown reasons.  But before we do that, there’s a last resort we may try.

Under Prepar3D’s program directory (version 4 or newer), there’s a shortcut called “Delete Generated Files“. 
It can quickly delete everything in your:

• C:\Users\<username>\AppData\Roaming\Lockheed Martin\Prepar3D v4 (v5)
• C:\ProgramData\Lockheed Martin\Prepar3D v4 (v5)
• C:\Users\<username>\AppData\Local\Lockheed Martin\Prepar3D v4 (v5)

The first directory above is where the Prepar3D.cfg is stored.   The second is the location of scenery.cfg.   And the third one is Shaders Cache.

By removing everything in these three directories via the shortcut, we can start the simulator as new again.  This action many times helps fix various unknow issues.

But do remember to make a backup first as the action will delete EVERYTHING in the three directories.  This is not only just a safety measure but also we can compare and copy back what are good from the previous directories after removal.

Should you want to clear up the Shaders only, my Shader_Cleaner is still a good choice.