Sometimes the EDB file of the user can be deleted due to a sudden power outage, server crash, and can be various other reasons. So at this time to again re-access the lost database user need third-party software. So I would like to suggest you go with this SysInspire EDB to PST Conversion tool which allows users to Exchange recover mailbox from EDB without making any reduction in the database.
For More Info:- Exchange Recover Mailbox from EDB