An Exchange Server database may not mount when it is inconsistent, corrupt, or damaged. You can check the database status by using the Eseutil /mh command. If the database is in a Dirty Shutdown state, you can perform a soft recovery or a hard recovery.

The database may also fail to mount due to the following reasons:

• Low disk storage
• Missing log files
• Some Exchange services are not running or working

However, some other factors could also prevent you from mounting the Exchange Server database. For instance:

• The Domain Controller policy is blank or missing.
• The server is no more a member of the Exchange Server group.
• The DomainName or Exchange Servers group doesn't have the manage auditing and security log permissions.

In such cases, when you try to mount the Exchange Server database, you may encounter the following error in the Exchange Management Shell or EAC.

Failed to mount database 'Mailbox Database.'

Mailbox Database

Error:

Exchange is unable to mount the database that you specified. Specified database: DatabaseGUID; Error code: MapiExceptionCallFailed: Unable to mount database. (hr=0x80004005,ec=-2147467259).

Also, an event is logged in the Application log with Event ID 9519 or Event ID 9518.

Event Type: Error

Event Source: MSExchangeIS

Event Category: General

Event ID: 9519

Date: date

You will also notice performance issues, and it may take longer to sign in to the server and computer to apply the settings.

In this guide, we have shared a few methods that you may follow to resolve the error 0x80004005 in Exchange Server and mount the database.

Methods to Resolve the Error 0x80004005 in Exchange Server

Follow these methods to resolve the error 0x80004005 that appears when you try to mount an Exchange database.

Add Exchange Servers Group to Manage Auditing and Security Log Policy

Login to your Domain Controller with an administrator account or user account that has administrative rights, and then follow these steps:

• Click Start and open Administrative Tools.
• Open and navigate to Domain Controller Security Policy > Local Policies > User Rights Assignment.
• Open Manage auditing and security log and click Properties.
• Click Add User or Group.
• Enter the <Domain Name>Exchange Servers and click OK > OK > Exit.
• Once done, wait for a while and allow the changes to take effect across DC.
• Then restart Microsoft Exchange Information Store

Now try mounting the database and check if it mounts or still displays Event ID 9519 and error 0x80004005.

Run Setup /PrepareAD Command to Restore Server Configuration in Active Directory

In Exchange Server 2016 and 2019, follow these steps to fix the Active Directory configuration and resolve the error 0x80004005 in Exchange Server.

• Download the Cumulative Update currently installed on your server and mount the ISO file. You may also navigate to the location where Exchange Server is installed to access theexe.
• Open the Command Prompt as administrator and use the cd command to navigate to the location where Exchange Server 2016 or 2019 exe is located. For instance:

cd F:/ (if using CU ISO)

cd C:Program FilesMicrosoftExchangeV15Bin

• Then run the following command to restore the server configuration in Active Directory.

Setup.exe /PrepareAD /IAcceptExchangeServerLicenseTerms_DiagnosticDataOFF

In Exchange Server 2013, follow these steps to prepare Active Directory:

• Download the Cumulative Update and mount the ISO file to access the Exchange Server 2013 installation files.
• Then open Command Prompt as administrator and navigate to the location where Exchange Server 2013 installation files are located using the cd For instance,

cd F:/

• Then run the following command to restore the server configuration in Active Directory.

Setup.exe /PrepareAD /OrganizationName:'' /IAcceptExchangeServerLicenseTerms

In Exchange Server 2010 and 2007, you can follow these steps to learn how to prepare Active Directory.

• Start Exchange 2010 or 2007 and click Help.
• Click the Contents tab, expand Deployment > New Installation > Preparing to Deploy Exchange 2007.
• Find and click on How to Prepare Active Directory and Domains.

You may also use the following command in Exchange 2007 or 2010 to prepare AD.

• Navigate to the location where Exchange is installed. The Setup.exe is located in the Bin directory.
• You may also use the CD, press Windows + R, and type

:Setup /PrepareAD

• Press the Enter key or click OK.

After performing this, restart the server and try mounting the database. It should mount now. However, if the database still doesn't mount, you may need to move mailboxes from the database to the new database copy.

For this, you will need an Exchange recovery software.

Use Exchange Database (EDB) Recovery, Tool

An Exchange recovery tool, such as EseUtil or Stellar Repair for Exchange, can help you recover an Exchange database that does not mount or is corrupt.

With EseUtil, you can use the following commands to try to recover the database and mount it.

Eseutil /mh (Check the database state)

Eseutil /r (Soft Recovery)

Eseutil /p (Hard Recovery)

Hard Recovery is not recommended as it recovers the database by purging irrecoverable mailboxes. This can lead to data loss.

Instead, use the Exchange recovery software — Stellar Repair for Exchange — to restore user mailboxes from corrupt or damaged Exchange databases to a mounted database on your live Exchange Server. You may also export them directly to Office 365 tenant or save them as PST files.

The steps are as follows:

• Install and launch Stellar Repair for Exchange.
• Select the EDB file for the scan. It will list all mailboxes and mail items.
• Select the mailboxes, click Save, and choose Export to Live Exchange.

• Enter the credentials and map the mailboxes to user accounts or create new ones within the software interface.
• Click Export.

After restoring the mailboxes, users can access their mail items and email account in Outlook and send/receive messages.

To Wrap Up

When the database dismounts due to inconsistencies, corruption, or any other reason, users having their mailboxes in the database cannot access their emails or send/receive new messages. In such a critical situation, you need to act swiftly to resolve the issue with the database and mount it to Exchange Server (Check how to change DNS Server). However, if the database doesn't mount even after recovery or displays the error 0x80004005 when you try to mount it, follow the solutions discussed in this guide to resolve the error and mount the database.