IS-0001 or LS-0018 when attempting to download an update
This error occurs when you are attempting to download a product that is already running on your computer. Most often, this happens when attempting to update Unreal Engine or one of our games while it is already running. Save your work if necessary and close the product, then you should be able to update successfully. If you continue to have trouble or the program is not currently running on your computer, reboot your computer and try again.