What Are MBOX Files? And How Do You Use Them for eDiscovery?

18 October 2021 by Ross eDiscovery MBOX

Takeaway: MBOX files are one of the most popular formats for storing groups of email. They’re extremely easy to use (you can open them with any basic text editor), but for eDiscovery, make sure you open them with dedicated eDiscovery software. This will protect file metadata and give you a host of great eDiscovery review tools.

Emails are a large part of most eDiscovery productions. So, how do you collect them in bulk?

With older ‘paper’ discovery, a production request meant going to your client’s office and collecting boxes of paper files. But nowadays, we receive virtual production requests and collect electronically stored information (ESI) – like emails – over the internet. This is convenient as all that data takes up less space. But it complicates things because it’s tricky to transfer emails from your client’s inbox into your eDiscovery software. For one, you might mistakenly change email metadata (more on this in a bit). But you also might split up email threads or lose attachments during the transfer. So, how do you collect eDiscovery emails in bulk?

MBOX files are a family of related formats designed to store and share emails. The four variations of the basic MBOX file – MBOXO, MBOXRD, MBOXCL, and MBOXCL2 – are all built on the same core structure but are formatted differently. They aren’t always compatible with each other but are still perfect for storing emails and their attachments. (Note: There are other ways of storing groups of email – like the MH Message Handling System or Outlook’s Microsoft Exchange Server. But MBOXes are still one of the more popular formats.)

MBOXes are text files that open with any basic text editor. And they store all your emails in sequence, as plain text.

MBOX files are a database of emails. But they’re really just text files that you can open using any basic text editor like Notepad++ on PCs and TextEdit on Macs. (This means you always have the option of quickly scanning through your emails without using an email client.) All your emails will be listed in the MBOX text file, with lines separating them from each other. Each email entry starts with the sender’s email address, followed by other information like when the email was received. And it ends with the email’s body content.

Gmail is perhaps the most famous MBOX user. And it offers a simple ‘export’ feature for your mailbox.

There are about a dozen email clients that use the MBOX format. For example, Mozilla Thunderbird, Mac/Apple Mail, Opera Mail, Spicebird, Entourage, Eudora, and more. But Gmail is perhaps the most popular of these. And it makes it so easy to download your mailbox. Just go to Google Takeout, click on the Gmail app from the list displayed, and use the ‘export’ feature. (You can choose to export all your emails or only those with a particular label.) You’ll then be able to download a ZIP file with the MBOX inside. Here’s a detailed guide to exporting emails from Gmail.

So, how do you open an MBOX file? There’s a range of options but for eDiscovery, it’s best to use a dedicated eDiscovery application.

You can open MBOXes using text editors or any of the MBOX-compatible clients listed above (like Thunderbird, Apple Mail, etc.). Or you can convert it to an EML file and open it in Outlook. But these aren’t ideal for eDiscovery. Instead, use dedicated eDiscovery software because it comes with the following advantages.

  1. You can protect email metadata. Metadata is the contextual information that’s tacked on to every file your computer creates. For example, if you create a PDF, its metadata would include information like when it was created, who created it, when it was last opened, and so on. This ‘data about data’ is like a digital footprint that shows you the file’s history, where it’s traveled, and how it’s been modified. But you can alter metadata without realizing it unless you use eDiscovery software. For example, opening an MBOX file using a text editor is quick and convenient, but it’ll change the file’s ‘last opened’ metadata entry. In contrast, eDiscovery software would let you open and review the file without changing its metadata entries. Learn more about metadata.
  2. You get an array of review tools. eDiscovery applications come with a well-structured toolkit. So, you’ll be able to make very specific ‘advanced’ searches, tag related emails, redact privileged information, and communicate with your team using notes, annotations, and comments.

If you haven’t yet found MBOX-friendly eDiscovery software, try GoldFynch.

GoldFynch is a Cloud-based eDiscovery service designed for small and midsize law firms. It’s easy to open MBOXes using GoldFynch (without changing metadata), and you get all the key eDiscovery tools you’ll need. But GoldFynch is great for other reasons, too:

  • It costs just $10 a month for a 1 GB case: That’s significantly less than most comparable software. With GoldFynch, you know what you’re paying for exactly – its pricing is simple and readily available on the website.
  • It’s easy to budget for. GoldFynch charges only for storage (processing is free). So, choose from a range of plans (1 GB to 150+ GB) and know up-front how much you’ll be paying. You can upload and cull as much data as you want, as long as you stay below your storage limit. And even if you do cross the limit, you can upgrade your plan with just a few clicks. Also, billing is prorated – so you’ll pay only for the time you spend on any given plan. With legacy software, pricing is much less predictable.
  • It takes just minutes to get going. GoldFynch runs in the Cloud, so you use it through your web browser (Google Chrome recommended). No installation. No sales calls or emails. Plus, you get a free trial case (0.5 GB of data and a processing cap of 1 GB), without adding a credit card.
  • It’s simple to use. Many eDiscovery applications take hours to master. GoldFynch takes minutes. It handles a lot of complex processing in the background, but what you see is minimal and intuitive. Just drag-and-drop your files into GoldFynch, and you’re good to go. Plus, you get prompt and reliable tech support.
  • Access it from anywhere, and 24/7. All your files are backed up and secure in the Cloud.

Want to find out more about GoldFynch?