How to convert Maildir to Mbox (without data loss)

Aid4Mail is the best Maildir to Mbox converter software on the market. Compared to competing tools:

  • Aid4Mail is faster.
  • More accurate with no data loss.
  • Offers more control over the conversion process.

If you don’t have Aid4Mail yet, you can use the free trial version or purchase a low-cost 2-week Aid4Mail Converter license.

Aid4Mail makes it easy to convert Maildir to mbox without giving up accuracy or speed. It specializes in processing email: converting from one format to another, searching, extracting and restoring mail, and exporting it in useful ways. We have been developing Aid4Mail for 20+ years and have lots of experience with converting Maildir files.

Please follow the steps below to convert mail from a Maildir file to mbox with Aid4Mail. For any setting that’s not specifically mentioned, you can either use the default (preset) value or consult the Aid4Mail 5 User Guide for details. You can open it from Aid4Mail by pressing the F1 key.

Step 1: Open Aid4Mail’s settings

Aid4Mail settings showing the session name set to "John Doe Maildir to Mbox". The Source and Target sections are expanded but not set. The Filter section is not expanded.

  1. In Aid4Mail, select the Settings tab.
  2. Update the Session name so it describes the task at hand. In this example, we will be converting John Doe’s Maildir files to Mbox so we’ve entered John Doe Maildir to Mbox as the session name.
  3. Below the session name there are three sections: Source, Target and Filter. Each can be displayed or hidden by selecting the +/- symbol next to the section heading. This tutorial requires them all to be displayed.

Step 2: Set Maildir as your source

Source settings for the Maildir format.

  1. In the Format list, select Maildir.
  2. Specify the Location of your maildir files. You can write it directly in the field or use the Select button to browse your file system.
  3. Choose whether to Remove journaling envelope if your email files are journaled.

Step 3: Set Mbox as your target

Target settings for the Mbox format.

  1. In the Format list, select Mbox files (generic mailbox).
  2. Choose whether to Export to a single mbox file, or create one mbox file for every mail folder.
  3. Set the Location where you want your mbox file(s) to be saved. You can write directly in the field or use the Select button to browse your file system. If you’re exporting to a single mbox file, set a file name (with or without an extension), otherwise set a directory location.
  4. Select an option for the Folder structure of the exported mail. Usually you’ll want to keep it the same as the original, so choose Same as source folder structure.
  5. If you want to add to existing mbox files, choose Append messages to target file if it already exists.
  6. Add extra metadata to email headers when your chosen target format or settings would otherwise result in data loss. For example, if the target format doesn’t support some of the source format’s header fields. Or if the original folder structure would be lost due to your settings. With this option, the data is not lost but instead added to the email headers.

Step 4: Set your filter (optional)

Filter settings showing a folder selection.

  1. Under Folder filtering, pick Folder selection. Your maildir folder structure will appear in the box below.
  2. Select the folders you want Aid4Mail to process. The others will be skipped.

Step 5: Run your Maildir to Mbox conversion

Session > Run menu command. The Run button is also visible on the button bar.

Select the Run button or Session > Run from the menu. Aid4Mail will convert your chosen maildir files to mbox. It will automatically open the Progress tab so you can monitor what’s going on. Once finished, you will find full reports in the Progress log and, if relevant, the Error log.

That’s it!

We hope you found this tutorial helpful.

If you’re looking for further information, first take a look through the Aid4Mail 5 user guide and our knowledge base articles.

If you still have questions, don’t hesitate to contact our award-winning Helpdesk.

If you’d like to buy an Aid4Mail license, please visit the online store.

Or if you’d like to try Aid4Mail first before purchasing, download a free trial and run your own tests converting Maildir to Mbox. We want you to have full confidence in Aid4Mail!

About Fookes Software

Fookes Software Ltd
La Petite Fin 27
1637 Charmey (en Gruyère)
Switzerland

For over 25 years we have been developing award-winning tools and productivity software. We also have more than 20 years of expertise in the field of email processing and analysis.

Our clients include Fortune 500 companies, government agencies, law firms, universities, and professionals specializing in e-discovery and forensics from around the world.

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