If you receive Error E03016 while attempting to update the NCSOFT Game Launcher please do the following:
First, uninstall the current NCSOFT Game Launcher.
Once you have uninstalled the Launcher you then need to install the stand-alone NCSOFT Game Launcher, you can do so by downloading the installer from this link here and save it to your Desktop.
Right-click on the nc-launchersetup.exe and select Run as Administrator.
Follow the prompts to install the program.