[Solved] How to Import MBOX to Office 365?

Jackson Strong | January 5th, 2023 | Email Migration, Office 365

I want to import MBOX to Office 365 Online account. Unfortunately, there is no option available in the admin panel. I had contacted Microsoft tech center but got no satisfied result. Do you have any workable solution to export MBOX to Outlook 365 webmail account?”

– Roman Atwood (Australia)

“Where can I get MBOX to Office 365 Migration Tool/Solution? I am working on Windows 10 machine/64 Bit and wondering about the alternate way to export .mbox file into O365 Online account. Kindly help me by providing automation solution. I have 12 GB of mailbox file.”

– Jordan Methew (Sri Lanka)

Want to migrate .mbox file to Office 365 Webmail account? Then you had landed in the very right place. At the end of this article, you will be able to migrate mailboxes to Office 365 account in one click. Yes, no need to struggle with manual processes. So let’s begin with the perfect way to upload MBOX file into Office 365 account.

Methods to Open MBOX File in Office 365 – Top 2 Solutions

There are two ways to import MBOX to Office 365 account. We have provided both manual and professional solutions to upload MBOX to Office 365. You can choose any of these methods according to your needs and requirements.

Method 1: How to Import MBOX to Office 365 Online? – Professional Approach

As there is no official method to convert MBOX to Office 365 account available. So it becomes almost impossible to upload MBOX file in Office Online. However, there is one perfect alternate option is available, especially for Office Small Business users.

Download and Install Advik MBOX Converter software in your Windows machine. This tool is specially designed to export MBOX messages into Office 365. You can upload large-sized .mbox files without facing any glitches or errors.

Note: Enable Less Secure Apps in Office 365. Click here to for the instructions.

Follow the below steps to Import MBOX to Office 365 webmail account;

Step 1. Run Advik MBOX Converter in your system.

Step 2. Click “Select File” and locate the .mbox file in the panel.

migrate mbox to office 365

Step 3. Choose “Office 365” as a saving option from the list.

import mbox to office 365

Step 4. Enter Office 365 login credentials.

upload mbox to office 365

Step 5. Click the “Convert” button and analyze the process.

mbox to office 365 migration

Done! This is how you can import MBOX file to Outlook 365 account. Now open your Office 365 webmail account and access complete data of the Mailbox archive. This is one of the widely opted solutions for MBOX to Office 365 migration purposes.

Now watch a video guide that will surely explain to you how to perform this task even more effectively.

Why Choose MBOX to Office 365 Migration Tool?

  • Simplest User-Interface for Non-Technical Users
  • Batch Import MBOX to Office 365
  • Maintain mailbox folder hierarchy and key elements
  • Preserve Metadata and other mailbox items
  • Repair MBOX file using same utility
  • (Special Feature) Convert MBOX to 10+ file formats
  • Unlimited migration (with No maximum file size limitation)

Download FREE Tool and Import MBOX to Office 365 Online

Method 2: How to Upload MBOX to Office 365? – Manual Solutions

The only manual solution to import MBOX to Office 365 is to configure Office 365 account with Thunderbird. As we know, Thunderbird can easily import MBOX files to its account. So let’s start with the step-by-step process.
The whole process is divided into two main steps, so don’t forget to follow each one individually.

Step 1: Add Office 365 account to Thunderbird

1. Launch and run Mozilla Thunderbird in your system and tap “Skip and use existing email”.

2. When setting up the email account, enter your name, your Office 365 email address and your password and tap the “Next” button.

upload mbox to office 365

3. Enter the following details to configure it manually;
For incoming:
Protocol – IMAP, Server – outlook.office365.com, Port – 993, SSL – SSL/TLS, Authentication – OAuth2, Username – Office 365 email address

For outgoing:
Protocol – SMTP, Server – smtp.office365.com, Port – 587, SSL – SSL/TLS, Authentication – OAuth2, Username – Office 365 email address

Now click on “Done” to carry out the configuration automatically.

import mbox to office 365

Step 2: Import MBOX to Office 365

1. Restart thunderbird and install “ImportExportTools NG” in your system.

open mbox file in office 365

2. Select the mailbox folder that you want to import to Office 365.

3. Right click on the folder and select ImportExportTools NG>> Import MBOX file.

upload mbox file to office 365

4. Now navigate to MBOX file and upload it to Office 365.

5. Select this MBOX file and click “Copy to >> Office 365 Account”.

import mbox to office 365

In this way, you can manually import MBOX to Office 365 via Thunderbird.

Related Article: Import MBOX to Outlook.com

Below are some of the related queries which can get resolved using the above method.

“I am looking for MBOX to Office 365 Converter Tool for Windows. Please suggest.”

“What is the quickest method to upload mbox to Outlook 365?”

“Is it safe to import MBOX files to Office 365 using this Migrator?”


Overall, Advik MBOX to Office 365 Migration Tool is an ultimate solution to transfer data from mailboxes. The best part of the tool is that it never modifies the mailbox structure as well as email layout. You will get the exact data with attachments.