How to Export or Move Emails from Thunderbird to MS Outlook / Office 365

There are a variety of emailing platforms and every organization uses one that suits its purpose, is easy to manage and is within budget. However, with time, organizations may face the need for a better platform. Let us consider an example. Thunderbird is a free open source emailing platform that is ideal for small businesses or personal emailing purposes.

But with growth, a company using Thunderbird might want to switch to a more sophisticated platform like MS Outlook. To perform the said switch, an organization needs to incorporate one of the many email migration techniques.

Now, when we talk about email migration, it is a rather tedious task that requires meticulous planning and a good amount of investment. Additionally, with the large number of mailboxes that need to be moved, there might often be chances of errors resulting in data loss. Thus, an organization must ensure that it performs the migration in the safest, most accurate way possible and within minimum time.

This article takes our discussion forward by covering a few techniques to perform Thunderbird to Outlook / Office 365 migration safely and precisely.

About Exporting Thunderbird to Outlook / Office 365

When email is exported from one platform to another, what basically happens is the conversion of mailbox contents within one type of database file into another type of database file. To successfully migrate email two phases of operations are required: an export from the source email platform, and an import into the destination email platform.

In the case of Thunderbird to Office 365 / Outlook, this involves the conversion of MBOX file to PST format. Thunderbird stores all contents within MBOX files and generates an individual file for each mailbox folder. Whether you need to migrate Thunderbird to different Outlook versions (2016, 2013, 2010, 2007 & 2003), the conversion process stays the same. The MBOX files storing Thunderbird mailbox folders and converted into PST format files that can be directly imported into Outlook / Office 365.

Methods to convert MBOX files into PST format

Here are the most widely used methods to perform Thunderbird to Outlook as follows:

1. Using IMAP

Internet Message Access Protocol or IMAP is an Internet standard protocol that allows 2-way synchronization between the email client you use and another online email account. It is designed to access the same account from multiple email clients. Thus using this protocol to perform this conversion is a good idea.

Here are the steps to do this:

  1. Use IMAP server to configure your Gmail account in Thunderbird
  2. Create a new folder in Gmail and move the messages to be exported to it
  3. Now you can see all messages to be exported in your Gmail account
  4. Configure the same Gmail account in MS Outlook by using POP or IMAP server and download all emails there

Note: This method can be used to export a few emails only.

2. Using Drag-and-Drop method

This method performs the export in two phases: one – export Thunderbird messages to EML files, two – import EML files into Outlook.

(a) Export Thunderbird messages to EML

  • Select messages to be exported from Thunderbird
  • Create a new folder on Desktop
  •  Drag all of select emails and drop into the folder on desktop

(b) Import EML files into Outlook

  •  Open Outlook
  •  Navigate to the folder where you wish to import the Thunderbird messages
  •  Drag all contents of the desktop folder into the Outlook folder.

Note:  This method works only with Outlook 2010 and earlier versions. Moreover, though this method is free of cost, it is not preferred since it takes a lot of time.

Drawbacks of the above two methods
In addition to the shortcomings of each method described above, they suffer from another significant drawback of the chance of data loss. Moreover, these methods don’t convert the MBOX data into PST format. So, they won’t work in case an organization wants to convert Thunderbird to Office 365.

Thus to steer clear of trouble, the next method is the most recommended one.

3. Using a third-party tool

With more and more organizations embracing Office 365 as their primary emailing platform, migrating mailboxes from on-premise setup to the cloud has become quite common. And effectively, the switch proves to be beneficial in many aspects – easier management, lesser investment and scalability. Organizations using Thunderbird too are moving to Office 365, and thus, a tool that can convert Thunderbird database files (MBOX files) to Office 365 compatible files (PST files) is the need of the day.

While the above mentioned methods also convert MBOX files into PST format, they suffer from many limitations already described above. Moreover, these methods can prove to be a little too complicated for new users and might result in data loss.

Final Opinion

Migrating emails is a complicated task for users who are not familiar with the technicalities of platforms. Plus, manual methods suffer from the limitations of being time-consuming and risky. They aren’t effective for Office 365 too. To get better understanding, You can try free demo of third-party MBOX to Outlook converter like MBOX to PST converter – Technician.

It is quick, safe and converts all data accurately into Outlook / Office 365 compatible format.Moreover, it gives you the option to append the converted data into an already existing PST file or create a new PST.

This competent tool converts MBOX data files from Thunderbird as well as other email clients such as Entourage, Spicebird, Pocomail, AppleMail, Eudora, Mulberry, SeaMonkey, Netscape, ClawsMail, OperaMail, Mozillamail, Evolution, Sylpheed, Cone, Mutt etc into Outlook / Office 365 compatible PST files.