The other day, I moved a client’s domain from one ISP to another; from A to B. That involved moving their email addresses as well, while keeping them identical between the previous ISP “A” and the new ISP “B”.
Convenient as that is for the client, there’s one issue: all their email prior to the move are still on IPS “A”. After the move, if they look for their mailboxes, they will all be empty.
Not a good thing.
Here’s how to move their old emails to the new service provider:
(You can do this on your own computer, BTW.)
Create two email accounts, one for the old ISP “A”, and one for the new ISP “B”. Obviously, the will be identical – same name; same password; and same address.
With one exception.
for ISP “A” -the previous ISP- the server address must not be the URL, the domain (which now points to the ‘new ISP) but instead needs to be the IP address of the previous email server.
So, if you were moving “mycompany.com” to a new server, and the email account accessed “mail.mycompany.com” to do the transfer, you’d have the new one still use “mail.mycompany.com” but the account you make for the old one would be “123.222.476.930” or whatever the direct access address is. (That may not be an IP address per se; it might look more like “mailserve.oldip.net”.)
Then, using your mail client, log into both. Wait a bit until the old email populate the inbox for the old account, and then just drag and drop them to the inbox of the new account.
That’s all there is to it.
1) I suggest that you verify success by accessing the new account via webmail.
2) some email clients are better than others at mass moves. (MailMate for Mac has no troubles at all.) Outlook, OTOH, may required that you drag-n-drop in small batches.
As usual, YMMV. This worked for me without any trouble at all, but the risk of using any of my suggestions is entirely your own. Etc.