Using Thunderbird To Move Email Between Two Accounts
You have two different email accounts, and wish to move a trove of old messages from one account to the other.
If both accounts allow IMAP access, you can use an email client to access both accounts simultaneously
and move or copy emails from one account to the other.
Both accounts must have IMAP access enabled. IMAP is available with Gmail and Microsoft accounts (Hotmail, Outlook.com, MSN mail, et al)
but might have to be enabled in your account's settings.
IMAP access may or may not be available through other email providers, such as in-house email servers from some ISPs.
This demonstration will illustrate moving email between a Hotmail account and another Outlook.com account,
but the principles should be the same with other IMAP mail servers.
This demonstration presumes you intend to go back to your old ways of accessing your email, so to
avoid making permanent changes to your computer we will use Thunderbird Portable.
(Note: Click any image for an enlarged view.)
Double-click the file to launch the "installer".
Accept the defaults and let it run to completion.
This does not actually install anything, it merely extracts the contents of the download and places them in a folder on your desktop.
Once that has finished, open the newly created folder, and double-click ThunderbirdPortable.exe to launch the Thunderbird program.
The Welcome wizard will automatically launch.
You already have two email accounts, so click "Skip this" to proceed setting up Thunderbird for your first account.
Enter your first email address and password.
Since we're not going to be composing and sending email from Thunderbird, the "Your name" field doesn't matter.
Click the [Continue] button to continue.
Thunderbird will search its database to determine the server parameters.
In this example, it has automatically determined the correct settings to use for Hotmail's incoming and outgoing mail servers.
Make sure IMAP is selected, and click the [Done] button.
Thunderbird will then attempt to login to your account on that mail server.
If you have Two-Factor Authentication enabled for your email account, you may need to
check your account settings for a special "app password" or temporarily turn 2FA off.
If successful, the left pane will be populated with the existing folders in your account.
Now we need to add the second email account.
Right-click the account name (the "@hotmail.com" in this example) and select "Settings".
The "Account Settings" window will open.
In the lower-left of that window, click "Account Actions" and select "Add Mail Account".
You will be presented with another "Mail Account Setup" window.
Enter the email address and password for your second account, and
click [Continue] to proceed.
Thunderbird will again attempt to autodetermine the server parameters for your second account,
then login, and if successful you will be returned to the main Thunderbird window with both accounts now in the left pane.
Steps 9 and 10 are optional.
If you wish to keep the transferred emails separated from pre-existing email in account B, create a new folder.
This is done by right-clicking the account name and selecting "New Folder".
Choose a name for the new folder, then click the [Create Folder] button.
Now simply drag-and-drop messages back and forth between folders in account A and account B.
In this screenshot, an email message is being dragged from the "save" folder in account A to the "old emails" folder in account B.
Messages can be either moved or copied.
The message is now in the "old emails" folder in account B.
Since this is being done via IMAP, we are actually modifying the contents of the two accounts on the mail servers.
You can open your web browser, login to your accounts online, and verify the changes have actually taken place.
You can repeat to move or copy other email messages.
Thunderbird allows you to select multiple messages and bulk-move them from once place to the other.
Depending on how many messages you have to move, this may take some time.
Once you have moved everything you wish, you can close Thunderbird and return to accessing your email in your usual manner.
If you no longer need the Thunderbird program, just delete the folder from your desktop.