The most effective way to convert PST files into EML format is by using the BitRecover PST to EML Converter. It is specially designed for this task and ensures 100% safe conversion without data loss.

Steps:
1. Download & Launch BitRecover PST to EML Converter.
2. Click on Add Files / Add Folders to load your PST files.
3. The software will display all the folders and emails.
4. Choose the required items you want to export.
5. Select EML as the saving option.
6. Set a location to save the converted files.
7. Press the Convert button to start the process.
All your Outlook PST emails will now be available in .eml format, which can be easily opened in email clients like Thunderbird, Windows Live Mail, DreamMail, etc.