Open PST File into Thunderbird

Updated on July 13, 2023 by Deepika Singh

On this page, Regain software has brought different ways how a user can use their Outlook emails in Mozilla Thunderbird. Before moving towards How to open Outlook PST file in Thunderbird let us discuss MS Outlook and Thunderbird in brief.

Microsoft Outlook

Microsoft Outlook is available as part of the Microsoft Office suite, which is a Personal information manager. Although it is an Email application, it also includes a calendar, task manager, contact manager, note-taking, journal, and web browsing. Microsoft Outlook is a desktop-based email client that all big and small organizations use. It is the most preferred email client due to its easy, secure, and advanced functioning.

Thunderbird Mail

Thunderbird is an application developed by Mozilla Foundation, a desktop-based email client application. Mozilla Thunderbird is an open-source, cross-platform email client, news client, RSS, and chat client. Thunderbird can be used on multiple platforms like Windows, Mac, Linux, and Ubuntu operating systems. It is installed by default on Ubuntu desktop systems.

Due to Microsoft Outlook mail client's advanced functioning and rich features, its pay price is higher than other mail clients. So the users are moving towards a reliable and cost-effective mail client. Thunderbird is one of the mail clients most preferred by the users.

Reasons why users prefer to move Outlook emails into Thunderbird are:

Cross platform support: Mozilla Thunderbird mail client runs on multiple platforms like Windows, Mac, UNIX and Linux. It is installed by default on Ubuntu desktop systems.

Junk filtration: Filtering of junk files is quite well than other mail clients.

Multi language support: Mozilla Thunderbird client is translated into more than 50 different languages.

3 Methods to Import PST file into Thunderbird

Method 1: Export Outlook to Thunderbird when Running on Same Operating System

When you are running outlook and thunderbird mail clients on same system then follow the below listed steps:

  • i. Go to start and click on default program
  • ii. Go to ‘select your default program’
  • How to Import PST Files into Thunderbird
  • iii. Select Outlook from program and click on ‘set as default browser’ and click on save changes
  • steps to Export Outlook emails to Thunderbird
  • iv. Now Run Thunderbird and in open file menu option on top then click on Tools >> Import
  • Open PST Files into Thunderbird
  • v. Now you can select import everything or mails and click next
  • Manual Steps
  • vi. Next select Outlook as the file type and click next. Your files will be imported after completion click finish.
  • Manual ways to Import PST Files into Thunderbird

Method 2: Use Google Takeout to Export Outlook PST to MBOX

  • i. Open Gmail account and go to Setting >> Forwarding and POP/IMAP and select Enable IMAP > Save the changes.
  • ii. Run Outlook and go to file menu in Top bar
  • iii. Click on add account now enter Username and Password of Gmail account and press Enter
  • iv. Create new Folder and copy & paste the required Outlook files in that folder in newly configured Gmail account
  • v. Now login to Gmail account and open Google Takeout (
  • vi. Next select Mail option and deselect rest all the options from ‘select data to include
  • Use Google Take Out to Export Outlook PST to MBOX
  • vii. Next create archive of Google and once it is created you can download the ZIP file containing the Outlook data in the MBOX file format.
  • Convert by Using Google Take Out
  • Manual ways to import pst file to thunderbird
  • viii. Once after getting the link download the Google Takeout archive by clicking on Download.
  • Manual Guide
  • ix. After completion of download extract the Zip file to find the MBOX storing all your Gmail emails
  • Free and easy way
  • x. At last by using Thunderbird email client import the downloaded MBOX file.

Method 3: Professional Tool developed by Regain Software

By Using Regain Outlook PST Converter, users can quickly convert PST files to MBOX/ EML, which Thunderbird Email client supports. User can even repair their corrupt PST files using this tool. One more benefit of using this tool is that it smoothly migrate Outlook PST to multiple formats i.e., MBOX, EML, MSG, EMLX, vCal, vCard, and Office 365 Platform.

Following are the Steps to Convert PST files to MBOX format:

  • 1. Install and Run Regain Outlook PST Converter on your system
  • 2. Click on Browse to add the PST files and Click on next
  • Regain Outlook PST Converter
  • 4. Select the files which are to be exported and click OK
  • 5. Take preview of the files to confirm before saving in MBOX format
  • 6. Now from saving option select MBOX file format
  • Select Saving file format
  • 8. Now after selecting the format select the location where the files are to be saved
  • 9. Click export the process will be completed in few moments.
  • Export Outlook PST file to Thunderbird


  • Converts Outlook PST files into new PST, EML, MSG, MBOX, HTML, PDF, VCF, EMLX, ICS, and TGZ file format.
  • Allows migrating Outlook PST file to cloud server such as Gmail, Yahoo Mail,, GoDaddy, Amazon Workmail, Microsoft Office 365 account, and Live Exchange mailboxes.
  • Allows adding and converting multiple Outlook PST files to support other file formats in a single go.
  • Comes with filter option to filter unwanted and empty folders of PST files and split feature to set up a size for resultant PST files.
  • Supports converting password-protected Outlook PST file. Also, there is no restriction on adding large-sized Outlook PST file for conversion to other format.
  • Effectively recovers corrupted, damaged, or inaccessible Outlook PST files and deleted items of Outlook PST files.


So, on the above page, we have discussed the methods to open PST files into Thunderbird. 1 and 2 are the manual method for conversion, which requires some technical knowledge, and there may be some data loss during the complete process. And the 3rd method is by the use of Professional tool, there is no risk of data loss. With the help of this tool, the files are converted in an easy, quick, and secure manner. So for getting effective results in time, go for affordable and reliable third-party tool like Regain Outlook PST Converter.

Related Software: Looking for a software to Import PST files to Office 365 account or Exchange Server. Click here