Export Outlook Express Email to PST - Version 4.0 Outlook express single emails are saved in .EML format and Outlook is saves in .PST format. If you want to transfer the emails of Outlook Express to Outlook then you need to Export Outlook Express Email to PST for that you will require EML to PST Converter software. No need to get any additional technical knowledge to Export Outlook Express Email to PST with this program. Also in the conversion process the software sustains all the email properties such as metadata, formatting, attachments, etc. Export Outlook Express Email to PST using the full version of EML to PST Converter software for $49.