How to Migrate Your Email Using IMAP

• This article refers to a source email account and a destination email account:
  • Source refers to the email account containing the messages you want to sync to another account. In this example, we’re using [email protected] as the source account.
  • Destination refers to the email account that to which you want to sync emails from the source account. In this example, we’re using [email protected] as the destination account.
    

Step 1: Add the Destination IMAP Account in Your Mail Client

If you use only Webmail or a mobile device to access your destination email account, or if you currently use POP3 for the account, you will need to set it up in a desktop email client using IMAP in order to sync the messages. If you already have your destination email account (to which you’ll be transferring the emails) configured locally using IMAP in Thunderbird, Outlook, or Apple Mail, you can skip this step and proceed to Step 2.

Note: If you currently have the destination email account set up in your mail client using POP3, you will need to set it up in a different email client to proceed. Most modern email clients will not allow you to change the account type, and would require you to remove the POP3 account in order to set it up again as IMAP. You must not delete an existing POP3 account, because the emails are only stored locally — if you do, all those emails will be lost and will not be recoverable because they do not exist on the server. Simply download a new email client (such as Thunderbird if you’re using Apple Mail, Outlook, or a built-in Windows mail client, or use your operating system’s built-in mail client if you’re already using Thunderbird) and set up the account up in that client, leaving your existing mail client alone. Once the emails are synced to the server via this process, your existing POP3 account will automatically download them and you can continue using your normal email client.

1. In Thunderbird or an alternative mail client, add the destination email account by selecting File –> New–> Existing Mail Account from the application’s menu. Be sure to check the box for IMAP.

1. Once you’ve added the destination IMAP account, you should see the email address listed in your mail client’s account list, and its messages will appear in the account’s Inbox. Please note that it could take some time to download copies of all the account’s emails from the server, depending on how many messages are contained in the account and the size of attachments.

Step 2: Add the Source IMAP Account in Your Mail Client

1. In Thunderbird or an alternative mail client, add the source email account (the account containing the messages you wish to transfer) by selecting File –> New –> Existing Mail Account from the application’s menu. Be sure to check the box for IMAP.

1. Once you’ve added the source IMAP account, you should see its email address listed in your mail client’s account list along with the destination account. Please note that it could take some time to download copies of all the account’s emails from the server, depending on how many messages are contained in the account and the size of attachments.

Step #3: Move the Emails Between Accounts

At this point, you’ll see both email accounts (“[email protected]” and “[email protected]” in this case) listed in Thunderbird’s account list. To move the messages between accounts:

1. Click on the source account’s Inbox, and select all the messages.
   • In Thunderbird, you can go to the menu and pull down to Edit –> Select –> All.
   • Other clients may allow you to use Control + A or Command + A from within the message pane.
   • Another option is to click on the first message to select it, scroll down to the bottom of the list and then Shift + click on the last message to select them all.

1. Once you’ve selected all the messages, click on any one of the highlighted messages and — without releasing your mouse button — drag the entire selected list into the other email account’s Inbox. It can be slightly tricky in some email clients, so don’t worry if you don’t get it on the first try.

1. After successfully completing the previous step, you will see all the messages from both accounts in the destination account’s Inbox.

1. Repeat steps A through C for each folder you wish to copy over (Sent, Drafts, or any custom folders that exist on the source account.)
   • Should you wish to create a custom directory in the destination account to match a custom directory existing in the source account:
     • Right-click on the destination account’s name (sample.example.com in the image above) and select New Folder… from the list of options.
     • Give the folder a name matching the custom folder in the source account. If it asks you where to create the folder, you generally want to select Inbox.
     • You can now drag and drop messages from the custom folder in the source account to the matching custom folder in the destination account.
2. Now, thanks to the IMAP protocol, the messages you’ve moved from the source account (and any custom folders you created) will automatically be synced to the destination account’s server. It could take a bit of time to complete, depending on the number of emails and size of attachments involved.
3. At this point, we can confirm that the process was successful (or at least is in progress), by logging into the destination account via Webmail or in your preferred email client.

Note: If you normally use a POP3 connection for the destination account in your preferred email client, your POP3 mail client will download all the messages you transferred to the account’s Inbox as they are synced to the server. You may need to configure your POP3 email client’s settings to see any custom folders you created in the destination account, as custom folders typically will not sync automatically when using POP3.