Can not register Avast Antivirus Free.

Neighbor to download and install the product Avast Free Antivirus (Slovak version).
After the end of a product called him to get him registered. On the https://www.avast.com/registration-free-antivirus.php fill the fields marked http://avastfans.com/wp-content/uploads/2016/10/Avast-activation-code-4-300x208.png and sent Register for Free License Key. Page announced that he will be via e-mail sent to the license key.
After receiving the key like to register your product Avast Free, but ran into a problem - in UI interface by clicking on Register https://static.avast.com/support/kb/images/v2016/avkb9/en/register_1.png window opens which is the active window only for the paid version.
Nowhere it can not insert received a license key.
The product can not be registered!

Asus X55, Windows 7 64-bit, Google Chrome, Mozilla Firefox.

The latest version of avast free doesn’t need to be registered.

Licensing gets reworked, see: https://forum.avast.com/index.php?topic=198923.0

Interesting note.
How it is possible that after a FREE time antivirus (active) announces that the user is not protected (surveys today - one day after expiry date) - reports that is not protected (red) and calls the product (FREE) I registered - yet, as I wrote earlier - all done. I got an e-mail with the license key (which is not where to insert).
And after checking (my) his computer there is clearly noted that it is Avast Free Antivirus version 3.17.2291 (build 17.3.3443.0).

I have the same issue with a friend’s computer which has had avast free on it for 1077 days and is also now saying it is expiring.

I too followed the path of getting a new licence but the instructions in the email call out the procedure for the old version interface and likewise I could not find out where to insert it via the new interface.

Also I tried to uninstall the product to see if a clean install would solve the issue but the uninstaller hangs at the stage of deleting scheduled tasks.

In case it is relevant the computer is Win7 and Ii was running as the administrator on the machine.