Email migration and business email hosting: a guide

Migrating an email account from one provider to another can seem daunting: nobody wants emails to go missing on the day of the move, or for old messages, folders and contact lists to be left behind. With good preparation, however, the migration takes just a few hours, and users will hardly notice a thing.

In this guide, we’ll walk you through when and why it’s worth switching, how to prepare, the methods available for transferring your emails, how to time the DNS changeover, and what to check afterwards.

When is it worth moving?

My mailbox is full, and it cannot be expanded cost-effectively with my current provider.
Delivery issues: your emails often end up in the spam folder, or your provider’s server has been blacklisted.
Missing features: no adequate spam filtering, webmail, calendar or backup; nor can SPF, DKIM and DMARC be configured.
Separation: your email has been hosted on your website’s hosting up to now, and you’d like to separate it from the website so that a website migration or error doesn’t affect your emails.
Price or support team: expensive, slow or incomprehensible support team.

Preparation

1. Inventory

List the following:

all your email accounts and their passwords (or ask your old provider for a new password for the duration of the migration),
aliases, redirects and group addresses (for example, info@ → several colleagues),
automatic replies, filter rules,
the size of the mailboxes, so that the new plan is large enough,
those systems that send emails via the old server (website forms, online shops, invoicing software, printers, scanners).

2. The new service

Order your new email service and set up the same mailboxes on the new server, using the same addresses. aWh’s email hosting is available in hosting plans ranging from 5 GB to 50 GB, with daily backups, spam filtering, webmail, a calendar and an address book, from €10.88 per year (excluding VAT).

3. Reducing the TTL

A day or two before the migration, reduce the TTL of your domain’s MX record to 300 seconds (where your DNS is currently managed). This way, after the switchover, email systems will start using the new server within minutes, rather than hours.

4. Information

Let your staff know when the switch will take place and what they need to do afterwards (for example, new server settings on their phones).

Email transfer

IMAP synchronisation using a tool (recommended)

If both the old and new servers use IMAP, emails can be copied from one server to the other, along with their folder structure, without needing to access users’ computers. The most widely used tool for this is the free imapsync:

imapsync \
  --host1 regi-mailszerver.hu --user1 info@cegnev.hu --password1 'REGI_JELSZO' \
  --host2 mail.uj-szolgaltato.hu --user2 info@cegnev.hu --password2 'UJ_JELSZO'

Imapsync only copies missing emails, so it can be run several times: first before the migration (this transfers the old emails and may take up to several hours), then once more after the DNS changeover (this transfers any emails that arrived on the old server whilst the changeover was taking place). Many providers, including aWh, will carry out the transfer of mailboxes on request; to do this, open a ticket with the details of your old accounts.

Using an email client

For some email accounts, you can also transfer your emails using an email client (such as Thunderbird or Outlook): add both the old and new accounts via IMAP, then drag the folders from the old account to the new one. It’s simple, but it can be slow if you have a lot of emails, and it’s easy to make mistakes with large accounts.

Accounts using POP3

If users have previously downloaded their emails to their computers using POP3, their old emails will be stored on their computers rather than on the server. In this case, set up the new account using IMAP, and upload the old emails from the local folders in your email client to the new mailbox. Our article on choosing between POP and IMAP explains which protocol is best to use in different situations.

Address book and calendar

Export these from the old system (in vCard and iCalendar formats) and import them into the new one. If they are stored in your email program or on your phone, they will remain there too.

The DNS changeover

Email will only actually be migrated once the domain’s MX record points to the new server. Schedule this for outside working hours.

Run the first synchronisation and check that all mailboxes have been transferred.
Point your MX record to the new server. If you are also transferring your name servers to the new provider, please ensure beforehand that, in addition to the MX record, all other records (A, CNAME, TXT, SPF, DKIM, DMARC and validation records) are present in the new zone.
Update your SPF record with the new mail server, configure DKIM using your new provider’s key, and check that the DMARC record is in place.
In a few hours’ time, run the synchronisation again to ensure that any emails received on the old server during the migration are also transferred.
Don’t cancel your old service straight away: keep it running for a few days until you’re sure that all your emails are being delivered to the new server.

The guide on managing DNS records covers MX records and DNS; the steps for modifying an MX record in cPanel are described in the article on modifying MX records in cPanel.

Will emails be lost during the migration? No, not if the old server is still running: during the migration, some emails will still arrive on the old server whilst others will arrive on the new one; the second synchronisation will then collect them all. Sending servers will retry several times even in the event of a temporary error, so even a brief outage will not result in any emails being lost.

Reconfiguring the devices

Following the migration, users’ email clients and mobile devices will need to be reconfigured with the new server details: the incoming (IMAP) and outgoing (SMTP) server names, the ports (IMAP 993 SSL/TLS, SMTP 465 SSL/TLS or 587 STARTTLS) and the new password. The easiest way is to remove the old account and add it as a new one. We have knowledge base articles on how to set this up for Outlook, Thunderbird, as well as for iPhone and Android.

Don’t forget your website’s forms, online shop, invoicing software and any other systems that send emails via the old server: you’ll need to enter the new SMTP details for these as well.

Verification

Send an email from an external account (for example, a Gmail account) to all important addresses, and reply to them as well.
Check your aliases, redirects and automatic replies.
Check the source (header) of an email to see whether SPF, DKIM and DMARC all return a ‘pass’ result, or use a verification service (such as mail-tester.com).
Check back in a few days to see if any more emails are arriving at the old server; if not, you can cancel the service.

Common errors

If you only change the MX records and not the SPF, your outgoing emails will end up in the spam folder because the new server isn’t included in the SPF record.
Two SPF records: the SPF becomes invalid. Always combine them into a single record.
Forgotten aliases and redirects: emails sent to certain addresses are lost.
Small new mailbox: synchronisation is interrupted because the quota has been reached.
Old service cancelled too early: emails received during the switchover will be lost.
Name server change without transferring the entire zone: your website or a DNS record may go offline.

Summary

A well-prepared email migration takes a few hours’ work: taking stock, creating the new mailboxes, setting a low TTL, synchronising from server to server, changing the MX records, updating SPF/DKIM/DMARC, a second synchronisation and reconfiguring the tools. Only cancel your old service once all emails are arriving at the new server.

We can migrate your email accounts to aWh’s email hosting service on request. Take a look at our email hosting plans

Frequently Asked Questions

How long does it take for the migration of emails to complete?

Copying emails takes anywhere from a few minutes to a few hours, depending on the size of the mailboxes; the MX record change takes effect within a few minutes if you have reduced the TTL beforehand. The entire process can typically be completed within one working day.

Will my emails get lost if I change my name servers?

Not if the email records (MX, SPF, DKIM, DMARC) are also present in the new zone, and the old server is still operational during the migration. The second synchronisation will also transfer emails received on the old server during the transition period.

Will the folders and the ‘read/unread’ status be transferred?

With IMAP synchronisation, yes: both the folder structure and the flags on the emails are transferred.

What will happen to old emails downloaded via POP3?

They are stored on your computer. Once you’ve set up the new account using IMAP in your email client, you can upload them to the server, making them accessible from any device.

Do users need to do anything?

Usually, you only need to update your email client and mobile phone settings with the new server details. Your emails will be transferred via server-to-server synchronisation.

Are you moving your emails?

Yes, aWh’s hosting plans include a free migration service. Open a support ticket with the access details for your old email accounts, and we’ll transfer your emails for you.

Not recommended: the email hosting is intended for daily correspondence and has an hourly sending limit. For bulk mailings, please use our newsletter service.

email
migration
dns
guides