Solved: How do I delete Discovery mailbox and Health mailbox in Exchange Database?

Question

We have recently migrated to Office 365 in a Hybrid environment. We’re are now in the process of decommissioning the on-premises Exchange Servers. We urgently need to reclaim the storage the mailbox databases are using. We have two discovery mailboxes and 69 health mailboxes running on the entire estate.

• Question 1: Are the health mailboxes safe to delete on the database?
• Question 2: Could I take the DB offline and delete?
• Question 3: What is the safest way to delete some of these databases?
• Question 4: What is the best way to delete discovery search mailboxes?

Solution

You can delete the health mailbox by the following command: Get-Mailbox -database databasename -Monitoring | Remove-Mailbox

Or you can even delete the health mailboxes accounts from ADUC.

Execute below command to delete discovery search mailboxes: Get-Mailbox DiscoverySearchMail* | Remove-Mailbox

Or move to another database if you have one: Get-Mailbox DiscoverySearchMail* | New-MoveRequest -TargetDatabase "DatabaseName"