Open Microsoft Outlook on your Windows computer.
Export PST File:
Click on "File" in the menu.
Select "Open & Export," then choose "Import/Export."
In the Import and Export Wizard, select "Export to a file" and click "Next."
Choose "Outlook Data File (.pst)" and click "Next."
Select the folder you want to export (usually, it's your primary mailbox), and choose the option to include subfolders.
Click "Next."
Choose a location to save the PST file and provide a name for it.
Click "Finish" to export the data to a PST file.
Convert PST to MBOX:
To convert the PST file to MBOX format, you'll need third-party software. Tools like "PST to MBOX Converter" can help with this conversion.
Install and run the PST to MBOX converter.
Browse for the PST file you exported earlier.
Select the output folder where you want to save the MBOX file.
Start the conversion process.
Regards,
Peter