To convert PST to MBOX with attachments, you can use a PST to MBOX Converter tool, which simplifies the process and ensures all email components are transferred accurately. Most reliable converter tools support attachments, email formatting, metadata, and folder structures, which means you can retain the integrity of each email along with its attachments.

Here's a general outline for using such a tool:

1. Install the Converter Tool: Download and install a reputable PST to MBOX Converter tool on your computer.
2. Load PST Files: Launch the tool and import the PST files you want to convert. Many tools offer a drag-and-drop feature or a browser option to locate your PST file.
3. Select MBOX as the Output Format: Choose MBOX as the target file format to which your PST data will be converted.
4. Start Conversion: Initiate the conversion, and the tool will transfer emails along with their attachments into MBOX format.
5. Save and Access: Once converted, you can save the MBOX file and access it through MBOX-compatible email clients like Thunderbird or Apple Mail.

Using a reliable converter tool ensures your emails and attachments remain intact throughout the process.