My old pc died so in the interim I have been using 3cx with my old license key on a spare computer. I just got a new pc and want to migrate 3cx to it. So I did a backup of the old setup (which was on version 12 since my old pc had a 32 bit operating system). Then I installed version 15 on the new pc and restored the backup onto the new machine. It refused to let me activate because the key was associated with too many mac addresses (my original 3cx server, my spare machine and now the new pc). How do I tell it to forget the old mac address of my old machine and allow me to activate on my new pc? (In the meantime I have activated with the free license, but my license entitles me to pro features and maintenance and I don't want to lose those benefits.) Thanks.