Cannot access old version

Hi,

I have some old laboratory equipment that is managed over Teamviewer. There is ver8 Free. Whatever version of Teamviewer I try to access it, it says "remote Teamviwer is old, upgrade now". Funny thing is that this machine does not have nor mouse or keyboard connection.

What options do I have? I read that there are some licensing terms changed and that is the reason why even version 8 Teamviwer cannot connect to this machine.