How to Open MBOX File in Office 365 Directly?

Rollins Duke   
Published: May 10th, 2024 • 4 Min Read

Open MBOX file in Office 365: Today most businesses and corporates are frequently shifting from on-premises servers and email clients. This is due to the fact that in the past few years there has been a decent surge in the usage of cloud solutions as with it one can access their information from any place.

Also, cloud services offer updates automatically, decrease security hazards, provide more versatility, and limit information loss. Large numbers of on-premises email clients utilize the MBOX document format for messages. The email client that is utilized with Exchange Online in Office 365 (Microsoft 365). So, in this article, we will go into the in-depth solution of how a user can open MBOX file in Office 365.

Read More: Way to Know Print MBOX Files in Bulk

Manual Methods to Import MBOX File into Office 365

We all know Thunderbird supports MBOX file format. So, here we will take the help of the Thunderbird email client to connect the account. All the steps are mentioned below:

Step 1: Connect Both Accounts

  1. Download and run the thunderbird email client to import MBOX file into Outlook 365.
  2. After successfully configuration, now hit the “ALT” icon and choose the “Account Settings” option.
  3. Now hit on the “Account Actions” >> “Add Mail Account” option.
  4. And then, enter the login details of the Office 365 account and put the server details also.
  5. Lastly, hit the “Finish” icon to open MBOX file in Office 365.

Now install the “ImportExportTools” add-ones (if not installed). Simply click on the menu icon and choose the “Add-Ons and Themes” option and search for the add-ons in the search box.

Step 2: Upload the MBOX File in Thunderbird

  1. Restart thunderbird.
  2. And then, right-click on any folder and choose the “ImportExportTools NG” option.
  3. After that, select “Import MBOX File” and browse the MBOX file from the location.
  4. After the successful process, now right-click on the imported MBOX file and select the “Copy To” option and select the Office 365 account.

Now your MBOX file will successfully open in Office 365.

Drawbacks of using Manual Methods

  • Compatible with only Thunderbird MBOX email clients while there are many more email clients.
  • Requires numerous email client apps on a similar system.
  • You can’t transfer data other than emails like contacts, schedules, tasks, etc.
  • Manual mistakes coming with this solution can lead to data loss issues.

The Direct Solution to Open MBOX File in Office 365

The MBOX to Office 365 Migrator is the best tool for users to perform this migration task. It can directly open MBOX file in Office 365 account along with attachments. The tool has selected files & select folders options to upload single/multiple MBOX files. With this tool, users can move mailbox files into the latest Office 365 webmail in batch without size limitations. Now, let’s discuss the working process of the software.

How to Open MBOX File in Microsoft Office 365?

  1. Follow some simple steps to complete the process of importing MBOX files to Office 365:

    open MBOX file in Office 365

  2. First, install and launch the tool in your system. It provides dual options to add mailboxes.

    dual options

  3. Now, users have to select MBOX files and folders.
  4. After that, mark the check option on the required checkbox for selecting required folders. Then click on Next.

    check option

  5. Thereafter, select the Office 365 saving option from the given drop list.

    Office 365

  6. Now, enter the Office 365 account login credentials – login ID & Password.


  7. Finally, click on the Convert button to start the importing process of the MBOX file to Office 365.
  8. A completion message will pop- up on the screen and click on OK.

    open MBOX file in Office 365

  9. Now, users can view the resultant data in their Office 365 accounts.

Major Features & Capabilities of the Software

  • With this application, user can directly open MBOX file in Office 365.
  • The software allows its users to upload multiple MBOX files to Office 365 accounts.
  • With this application, users can choose only required MBOX folders to perform selective migration of MBOX files to Office 365 accounts.
    It supports all MBOX-supported Email clients.
  • The application moves mailbox files into the latest Microsoft Office 365 Webmail in batch without size limitations.
  • Users can select Files & select Folders options to upload single/multiple MBOX Files in bulk.
  • Here, admin Credentials are required to perform mailbox mapping of multiple Office 365 User accounts.

Ending lines

Here, we have discussed how to open MBOX file in Office 365. We have explained in detail both Professional and Manual methods. You can choose any of these solutions as per your need. But, as said above manual method is time-consuming and there is a fear of data loss in this method. So, it’s better to use automated software.