We should first emphasize that you should always make a full backup on your own computer of everything related to your mail programme before making any changes. Be sure to include messages and settings.

With the Apple Mail application, if a POP3 mailbox (an "account") is deleted, it removes all messages associated with that mailbox, deleting them from your computer — which may have the only copy of a message if you're not also storing them on our servers!

There are two kinds of mailboxes in Apple Mail — ones that sync with an associated email server (these will be your inbox, sent items, trash, drafts and junk) and "On My Mac" mailboxes that only exist on your Mac.

To ensure that you don't lose your email data when we delete your old email account copy all messages into an "On My Mac" mailbox before we delete your account (Note: your account will only be deleted on the day of migration).

First, make a new local mailbox to store the messages after your account is deleted. Go to Mailbox > New Mailbox and this box will show up:

Create a folder called:

1 inbox
2 sent items
3 trash
4 drafts
5 junk (if you want to keep your junk)

The folders will look like this once you've created them:

Now starting with your inbox, select all the messages. Drag them to '1 inbox' under On My Mac. Do the same for sent items, dragging them to '2 sent', Trash to '3 trash', drafts to '4 drafts' etc.

Continue to do this on a regular basis up until the date of your migration. In doing this, it will help to save time and improve the process when we switch your accounts over.