Steve on 09 May, 2022 01:52 PM
if you are looking to no longer use your old mac:
deactivate GPG Mail on your old mac by opening Mail > Preferences > GPG Mail and clicking the Deactivate button. You recoup your activation. (you can also keep using it as you can use GPG Mail on more than a single computer used by yourself)
this KB-article explains how to transfer keys to a second mac if you want to use the same keys on more than a single machine.
If your new mac is the only mac you will be using you should remove your keys from the old mac. Make sure to create a backup first (!) and double check your secret keys safely made it to your new mac.
Let me know if you have more questions or need further assistance after going through the steps.