ok grabbed new USB added pro.key, super.dat and pools folder also docker.cfg. Since this is a backup machine only had one vm and one docker for cloudflare. So no great loss.
Rebooted and prompts for registration key, go to page, click 'Replace Key', popup opens,log in, then that disappears with note to finalise the process by clicking on a further button which does not appear. as I was using firfox I went to Edge and the popup appears to Finalise but when I click that it just goes back to the previous popup and cycles over and over.
will probably have to contact support, unless there is further advice? thanks