If you are using Windows 10, then you need to be using version 2 of WCS. This is free to version 1 users.
To install version 2, you cannot use the built-in autoupdater. Version 2 is not an update to version 1, but a completely re-written piece of software. That means you need to download the full installation file for version 2 and install it on your computer. You can have v1 and v2 running on the same computer at the same time. They are totally separate!
To get version 2, you need to login to the download area. You were sent details of the URL, your username and password when you purchased WCS. It's the same place. Login there and download the v2 install. There are also instructions showing you how to import your v1 data into v2.