Switching email to a new suite: run both for a week, not a weekend.
A business switched email suites on a Friday night, planning to be done by Sunday. By Tuesday, a supplier's invoices were bouncing, a shared mailbox was missing its history, and two phones still pointed at the old server and showed nothing new.
Email is not one thing. It is the address, the mail records, every phone and laptop, shared mailboxes, and every outside system that sends mail as you. A weekend is enough to move the data. It is not enough to find out what you forgot.
Running both suites side by side for a week turns forgotten things into small annoyances instead of lost mail.
What to do
- List every mailbox, shared mailbox, alias and every device that reads mail.
- Set up the new suite and create all addresses. Copy the old mail across in the background.
- Turn on dual delivery if your setup allows it, so new mail lands in both places.
- Look at what actually arrives and when. Pick a cutover day and time when the fewest invoices and orders come in.
- Change the MX records. Keep forwarding from the old suite to the new one for at least another week.
- Move the devices one at a time. Check the printers, scanners and websites that send mail as you, since they often hold the old settings.
When not to
If your current email works and the only reason to switch is a feature you might use someday, do not switch. Also, if the mail host is changing but you are very small and have one mailbox, a single careful evening may be enough. Still test sending and receiving before you close the old one.