There is no way for a customer to change their own email
address in Kartris. The email address is assumed to be unique, and
therefore we use this as the username. To avoid various issues with
changing email addresses (including verification of the new account to
ensure that its owner accepts the change and the problem of existing
accounts), we have made changing email addresses a back-end only
feature at present. If a customer needs to change their email address,
then their only option is to contact the store owner so that an admin
can change it for them.
The Kartris
back end will check that the email address is not already in use (you
cannot have two accounts with the same email), but it will not check
that the owner of the new email address consents to the change (i.e.
that the person making the change owns the new account), or that
someone requesting the change (by telephone or email) is actually the
owner of that account.
For security reasons, you should always be careful when
customers request an email address change that you are absolutely
100% sure that the customer is the genuine owner of both email
accounts. The best way is to write to both the old and new addresses
separately and get a reply from both (a reply that includes your
original email text). It is vital that you don't inadvertently hand
control of an account to a third party due to lax security
procedures. Although they could not access credit card data, they
would be able to access personal details such as address and phone
number as well as order history.