Summary: Read this comprehensive guide to learn ‘how to migrate Mozilla Thunderbird mailboxes to Exchange Server’. The guide will explain manual method with step-wise instructions to perform the migration process. In addition, you’ll learn about a specialized tool that can ease the Thunderbird to Exchange Server migration process.
Mozilla Thunderbird is one of the popular email clients due to its open-source, cross platform nature. However, situations may arise when you need to transfer Thunderbird email files to Exchange Server.
While it’s easy to import Outlook PST file to Exchange Server, importing Thunderbird MBOX data file to the server can be difficult and time-consuming. To help you streamline the process of migrating Thunderbird mailbox data to Exchange Server, we will be covering the most efficient methods to perform the migration.
Manual Workaround to Migrate Thunderbird to Exchange Server
Note: This method applies to users having active Thunderbird and Outlook accounts. In case, you no longer have an active Thunderbird account but have all your mailbox data stored in an MBOX file, we recommend using Stellar Converter for MBOX software to perform the migration process. Download the free trial version of the software to validate its functionality.
Follow these steps to manually move Thunderbird to Exchange Server:
Step 1: Configure Outlook account in Thunderbird
In the first step, you need to configure your existing Outlook account in Thunderbird. For this, do the following:
Open your Thunderbird email application, and then open the menu bar as shown in the image below.
Click New from the menu bar.
Next, select Existing Mail Account.
In ‘Set Up an Existing Email Account’ window, fill in all the required details:
Name: Enter the name (which will appear to others when you send the email).
Email Address: Enter your Outlook email address.
Password: Enter password of your Outlook email account.
Hit the Continue button.
Thunderbird will automatically configure the email account you have just added.
Once the Outlook email account gets configured, click Done.
Step 2: ‘Drag and Drop’ Mailbox Folder from Thunderbird to Outlook Email Account
After successfully configuring your Outlook email account in Thunderbird, drag and drop the mailbox folders from Thunderbird email account to the Outlook account one at a time. Once you have added the folder in the Outlook email account, it can also be viewed directly from your Outlook account.
For example: In the image below, the folder named ‘Starred’ is visible in Thunderbird as well as Outlook email account.
Step 3: Export Mailbox Data to a PST File
Now, you need to export the data from the (Thunderbird) mailbox folder that is added in Outlook to a PST file. For this, perform these steps:
Open Outlook, and click File from the main menu.
Click Open & Export > Import/Export.
Choose Export to a file from the ‘Import and Export Wizard’, and then click Next.
Select Outlook Data File (.pst) from the ‘Export to a File’ dialog box, and hit the Next button.
Select the Thunderbird folder that you want to move to Exchange Server (which in our case is Starred), and then click Next.
In ‘Export Outlook Data File’ window, click Browse to select the location where you want to save the PST file.
In the window that appears, specify the PST file name and select the desired location to save the file, and then click OK.
The ‘Export Outlook Data File’ window will appear again. Select any of the options under the Options section, and click Finish.
You will be prompted to enter a password for the PST file.
Note: This is an optional step. Skip it to the next step.
The PST file will now get saved at the specified location.
Step 4: Import PST into Exchange Server
Lastly, you need to import the PST file data into mailbox in Exchange Server by using Exchange Admin Center (EAC). The steps are as follows:
Open EAC, and enter administrator credentials.
In ‘Exchange admin center’ screen, click Recipients > Mailboxes. Select a mailbox from the list of mailboxes that is displayed, click the More (…) Options icon, and then select Import PST.
When the ‘Import from a .pst file’ window opens, enter the UNC path (containing the network share folder) and hit Next.
In the screen that appears, select the target mailbox where you want to import the PST file. Press the Next button.
Finally, configure any of these settings:
Leave ‘Send email to the mailbox below when the .pst file has been exported’ checkbox checked. You can add or remove notification recipients by clicking Browse.
Clear the ‘Send email to the mailbox below when the .pst file has been exported’ checkbox.
Click Finish to complete the import process.
When you're finished, click Finish.
Problems Associated with Manual Method
While the step-wise instructions discussed above can help you transfer Thunderbird emails to Exchange Server, it has certain downsides:
Requires active Thunderbird account: You need an active Thunderbird account to transfer its data to the Exchange Server.
Lengthy and time-consuming process: It allows exporting only one (Thunderbird) mailbox folder to Outlook PST at a time. And so, exporting multiple mailbox folders to PST can take significant time and effort.
Risk of data loss: Migrating data from Thunderbird to Exchange Server manually involves data loss risk.
Does not support multiple file saving formats: The workaround does not provide multiple file saving options. You can only convert Thunderbird MBOX file to PST file format.
Migration of multiple MBOX email clients to Outlook is not supported: You can only migrate Thunderbird MBOX email client to Outlook by using the manual method.
Migrate Thunderbird to Exchange Server by Using Stellar Converter for MBOX
You can overcome the limitations of manual method by using a specialized Thunderbird to Outlook converter tool such as Stellar Converter for MBOX. Here’s how:
Converts MBOX file into PST file format without Thunderbird installation.
Allows exporting multiple MBOX files to PST in a single batch process.
Converts MBOX file to PST while keeping the data intact.
Allows saving MBOX file to multiple formats, such as PST, Office 365, RTF, PDF, and HTML.
Capable of converting multiple MBOX email clients such as Thunderbird, Apple Mail, Eudora, Mozilla Mail, etc. into PST.
The software streamlines and expedite the process of converting Thunderbird mailbox into PST. Once converted, you can easily import PST into Exchange Server. The detailed steps are as follows:
Install and launch Stellar Converter for MBOX software on your Windows machine.
From the software main interface window, select Thunderbird from the drop-down list of mail clients.
If you are aware of the MBOX file location, click Select File for selecting the MBOX file. If the location is unknown, click Find File to search and select the MBOX file.
Note: To select all the MBOX files in an identity folder, hit the Select Identity button.
Once you have selected the MBOX file(s), click Convert.
After completion of the conversion process, the software displays a preview of all Thunderbird emails. Click and preview emails and their attachments.
NOTE: The software needs to be activated to export the converted MBOX file into PST.
Click Save Converted File option from the menu bar under the Home tab.
Choose to save the converted file as a New PST file, and then click Next.
A ‘Choose Destination’ dialog box appears. Click Browse to select the location for saving the converted (PST) file, and then hit the Save button.
Click OK when the ‘Conversion Completed’ message box pops-up. Click the ‘Open Containing Folder’ link to view the saved file(s) at the selected location.
After converting Thunderbird MBOX file into PST, import the PST file into Exchange Server by using EAC (refer to Step 4 above).
The methods explained in this guide will help you quickly and efficiently migrate your mailbox items such as emails, contacts, calendar, etc. from Thunderbird to Outlook. Choose a method carefully considering your requirement and preference.
The manual step-wise approach can transfer Thunderbird email folders to Exchange Server one at a time and given that you’ve active Thunderbird and Outlook accounts.
However, if you want to migrate multiple mailbox folders from Thunderbird accounts to Exchange Server at one go, use a professional MBOX to Outlook PST converter tool such as Stellar Converter for MBOX. The software can convert multiple Thunderbird MBOX files to PST. Once converted, you only need to import the PST file into Exchange Server.