I purchased a master 22 last year. I purchased a master upgrade this spring, loading 23/32 and added the Registration again without issue. I followed the forum instructions and uninstalled the 23/16 version all together, and installed the 'new and improved' 23/64 version and that's where the fun began. However I tried to install the Registration code, or did the online restore doodad, nothing but 'this is not a MC number' or such was the only response. I contacted JRiver by email and was advised to follow the restore instructions. PS: there are no 23/64 instructions.
Trying seemingly everything (reloading latest 22/16 licence switching off virus detection, firewall, etc. I used all my restores. Of course now the trial period has shut me out with 'Restore has been tried too many times, despite it advising me there were 2 days left to 'try'.