When mail matters most.
BEFORE
List every mailbox and its size Identify which are actively used Note every forwarder and alias Note autoresponders Record MX, SPF and DKIM records Warn users of the change
MOVING
Create every account with the same address Transfer messages by IMAP, per mailbox Recreate forwarders and aliases Recreate autoresponders Verify folder structures transferred
THE TRANSFER
Start early. Large mailboxes take hours.
Do it before switching DNS, so mail continues arriving at the old server meanwhile.
AFTER SWITCHING
Test send and receive from every account Check SPF and DKIM under Email Deliverability Send to a major provider and check it does not land in spam
FOR USERS
Send instructions for reconfiguring their devices, with the new settings.
BEFORE CANCELLING
Check the old mailboxes for anything received during propagation.
Confirm every user has successfully reconnected.
