This error means that the Epic Games Launcher is unable to install or update your game.
By running the launcher as an administrator you ensure there are no permissions issues that could be causing the installation to fail.
Reinstalling your game may resolve the issue.
If verifying your game files doesn't resolve the issue you can try to manually remove your game files from your computer.
Note: The default installation directory is C:\Program Files\Epic Games\
Right-click on the game folder and click on Delete.
Restart the Epic Games Launcher.
Reinstall and try launching your game.