What is an Exchange database file?
An EDB (Extensible Storage Engine Database) is an Exchange database file that stores all of the mail data and allows you to retrieve and access information from Microsoft Exchange server, such as user mailboxes, public folders, emails, contacts, tasks, notes, journals, and so on. In normal circumstances, an Exchange server functions like any other email server allowing users to send and receive emails etc. However, when an Exchange server is inaccessible due to hardware failure, power failure, dirty shutdown, or malware attack, the Exchange database dismounts and is no longer accessible. In such scenarios, you must try to mount the EDB file to the Exchange server or recover emails from a dismounted Exchange database to access the mailbox data. A common reason for opening the EDB is when the Exchange server is no longer available (decommissioned) and you're left with an offline EDB file whose mailbox contents you'd like to recover.