Hello Kent (and everyone else helping out here),
It really is very simple. The confusion here is about regular account management, and it’s nothing specific about AxCrypt. It’s how all account systems work.
An account always has some kind of identifier naming it. Sometimes it’s your realy name, sometimes it may be your phone number – but the absolutely most common account name identifier is an email address. AxCrypt accounts use the email address.
This type of system typically also relies on access to the mailbox associated with the email address as ‘proof of ownership’. That’s why we and everyone else sends out these emails with a verification link. The link contains something unique, that when used ‘proves’ to the server that you actually have access to the mailbox associated with the email address.
So, if I go ot a site, and enter *your* email address (let’s say email@example.com), the account is created and an email is sent to *you*. I will never see it. You will see it, and hopefully just throw it away.
Or, you go to the site, register with your email (still firstname.lastname@example.org in this alternate example), get the verification email, click on the link – use it a little bit, and then forget about it. Years passes…
Now, you are at the site again, you register with a different email (let’s say email@example.com), get the verification email and complete the process. Then you realize that you’d after like to use firstname.lastname@example.org after all. So, you ask the site to change from ‘email@example.com’ -> ‘firstname.lastname@example.org’.
But, ‘email@example.com’ already exists on the server! The server has no real way of knowing that ‘firstname.lastname@example.org’ and ‘email@example.com’ are really the same entity. So, it tells you “Sorry, but that account is already taken”.
What to do?
Simple – since you are in affect both, just sign in to ‘firstname.lastname@example.org’ (if necessary reset the password, which you can do since you have access to the mail box), and then delete the account ‘email@example.com’.
Now, you can go back to ‘firstname.lastname@example.org’, and change the email to ‘email@example.com’ which is no longer existing, and thus the server allows the change.
The above procedure may differ in detail depending on the provider, but the core issue remains the same. In order to create, or move an account, you need to prove ownership of the account email. In the case of the change scenario, to both.