Having been Line 6 user for over 12 years, I am writing my first ever post on this forum to say thank you. Thank you very much!
After going round the houses for hours and trying many things, this was the solution that finally got my JTV connected to my computer.
For me, I skipped step one as I am not on a Windows 11 version that has those bitlocker settings. I followed all the other steps and it still worked like a charm.
From what I've read in various recent posts on this topic, I suspect this "fix" may work for many others.