There was a time a while back when it would do exactly what you’re seeing if you had a 3rd party hosts file that blocks parasite websites.

If you have replaced or augmented hosts, try renaming it briefly out of service, running the registration, then putting it back in place.

It’s a bit disturbing that Avast seems to need to talk to a site that MVPS has deemed a “parasite”, but I’ve not seen any harm come of registering Avast.

-Noel