Activation & reactivation problems seem to be many since the EU GDPR day (25th May 2018).

It is essential that DraftSight can access the server. It used to be www.solidworks.com but now we have to allow access to www.3ds.com. I do not know when it changed but unless the later address is specifically allowed registration will not be successful. On a network you may need permissions from your administrator to do this.

In Firefox, <> has to be added to exceptions on the Options/Privacy/Permissions page under "Warn you when websites try to install addons". This allowed me to register the latest version as soon as I had set the permissions.

A link for Internet explorer is here: https://www.itg.ias.edu/content/how-add-trusted-sites-internet-explorer and sites are on Google for other browsers.

This has to be the first step. No contact = no registration = no registration email = no Draftsight.

Once this is done, then explore other methods if this step fails to allow registration.

Hope this helps, and if it does, maybe someone can translate these instructions into other languages.