You can manually or professionally convert Maildir to MBOX. To do the manual conversion, use an email client such as Thunderbird. First, install ImportExportTools NG add-on. After that, place the Maildir files in the Thunderbird profile and use the add-on to export the files as MBOX format files.

The procedure is technical, long, and not suitable for mass data. It involves Thunderbird installation, poses a risk of data corruption, and does not directly support folder structure preservation or metadata correctness.

Another option is to use the DRS Softech Maildir Converter for Mac is a robust and universal tool. The software assists you in converting all your Maildir files into MBOX securely and effortlessly. Moreover, there is no limitation on the size of the data being converted. You can easily convert MBOX to Maildir even with no technical knowledge. Besides, it presents numerous stunning features such as conversion with or without attached files, conversion without duplicate emails, etc. Moreover, it will safeguard and deliver precise data without any limitation. You can refer to the below-working steps to achieve the process without any interruption.

1. Initially, open the DRS Softech Maildir Converter on your system.

2. Next, select the Maildir file to be converted to MBOX. Click Open >> Next.

3. Next, view the Maildir file content and mark the item that you wish to convert. Click Next.

4. Then, select MBOX file format as your saving type from the dropdown menu.

5. Now, specify the path where you wish to save your output MBOX file.

6. Lastly, click on the Convert button to trigger the Maildir to MBOX conversion process.

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