Moving MBOX Files to Office 365- Reasons and Steps

Pritam Majumdar
Pritam Majumdar | Updated On - 15 Mar 2021 |

Read time 7 min

Known more commonly in its short form, MBOX is a popular file format that is used in several desktop email clients like Mozilla Thunderbird, Eudora, Seamonkey as well as others. These MBOX files are used in all important platforms which include Windows, Mac as well as UNIX. This portrays the wide range of usage of the MBOX in the technological field. MBOX has been categorized into different variants namely, mboxo, mboxcl, mboxcl2, etc. Each of these variants are used by different email clients over the vast assortment of MBOX files. However, the most common variant used today is the .mbox extension.

Office 365 on the other hand, is a cloud-storage service which has been developed by Microsoft. Office 365 provides several online applications that the user can work with, all well-featured and accessible from anywhere and anytime. Its features are inclusive of the following: Storage of emails, contacts, to-dos as well as journals. Moreover, this cloud-storage service enables you to keep your data secure from those software that might cause your data harm.

Moving MBOX Files to Office 365? Why?

An Outlook user would always know that he/she cannot open an MBOX file directly. Additionally, as a user, you would also know how the MBOX files face certain errors while accessing these files. Following are a few of them:

  • The MBOX file does not exist or it has been moved.
  • Oversized MBOX Files
  • Unable to Load Emails

Due to these hindrances, users tend to go confused and therefore the necessity converting these files to a more dependable service arise. This is the reason why we need to move or import MBOX Files to Office 365.

Having that in mind, we need to realize there are basically two methods of importing MBOX files to Office 365, namely: manual & mechanical.

Steps to Move MBOX Files to Office 365

  1. Manual Method to Move MBOX Files to Office 365
  2. Using Tool to Convert MBOX to Office 365

Manual Method to Move MBOX Files to Office 365

  • Open Thunderbird application, configure your Gmail account.
  • Create new folder in Thunderbird where you can add the emails you wish to open in outlook
  • Create new folder in Thunderbird

  • Select emails which you wish open in your Outlook. Move them to the new folder.(Note: simply drag and drop them to the new folder or use Move to.)
  • Select emails

  • Now open Outlook and select the emails you wish to add on the Outlook
  • Pen Outlook and select the emails

  • Now drag the file to a new folder in Outlook. This way you can view these on the new folder.

Follow the above procedures if you want to use the manual method. However, this system might be both time-consuming and be filled with hassle. Therefore, it is advisable that you use the automated method via Kernel for MBOX to Office 365.

Using Tool to Convert MBOX to Office 365

We’ve seen how the manual method enables us to convert MBOX file to Office 365. But, it is not suitable for a large sized data where there are multiple mailboxes and you just cannot drag and drop each file. This necessitates the mechanical procedures and to provide such an aide, Kernel has provided the users with its Kernel for MBOX to Office 365.

Some reasons how Kernel for MBOX to Office 365 becomes indispensable to you as user, lies in the following facts:

  • The software is capable of exporting mailbox data from the MBOX/MBS/MBX files of 20 well-known email clients like Thunderbird, AppleMail, PocoMail, etc.
  • Further, if you’re using the tool you can move all your emails and your metadata to Office 365 maintaining absolute integrity of the same. Additionally, the software has a filtering option which segregates your items prior to migration. You can filter out the mailbox data with the following criteria: date range, from, etc.
  • Again, the Tool enables you to preview the entire mailbox data prior to exporting to Office 365. It also helps you to authenticate the integrity of the items which are being migrated along with the performing of selective migration.

Keeping these features in mind, we need to understand how this tool works. The following passage therefore explains the steps to use Kernel for MBOX to Office 365:

Step -1: Install & Run Kernel for MBOX to Office 365 software

Step – 2: On the Source file selection window, select from either one of the two: ‘Select folder’ or ‘Select File’. Click on the Browse button.
Select folder or file
Step -3: Select MBOX folder. Click Open.
Select MBOX folder
Click on Finish.
click on finish
Step – 4: Select either a singular folder or multiple folders and click on Save.
Select singular folder or multiple folders
Step – 5: In the ‘Select the output type to save the recovered data’ window, select Office 365 option. Click on Next.
Select the output type
Step – 6: A new Select Filter(s) window comes up. Here, you can easily put multiple filters like Item Type, Date-range, Folder Name, Subject, To, and from etc. After applying the filters, click Next.
Select Filter

(Note: If you Select ‘Selected only’ from the Include drop-down, you can select from either of the options.)
Press the Shift Key and select multiple items (or a single item). Click Next.

Step – 7: Input the Office 365 credentials and click Finish.
Input the Office 365 credentials
And your File is saved.

Kernel for MBOX to Office 365 Working Video



If you are also getting the errors while using the MBOX-based email client and want to upgrade to a better platform, then your Kernel MBOX to PST Converter software. It will scan the MBOX file for the possible corruption and then migrate the healthy data to Office 365. You can also choose the software to migrate MBOX emails to another email servers like Exchange, IBM Domino, and Novell GroupWise, etc.