Tag: MDO

How to Check if Shared Mailboxes Need MDO Licenses

Posted on by Tony Redmond
Microsoft Defender for Office 365 and Shared Mailboxes

Shared mailboxes might need Microsoft Defender for Office 365 licenses, but how do you identify how many licenses? We use PowerShell to do the job by analyzing external email sent to shared mailboxes. If a mailbox receives external email, then by definition the mailbox receives benefit from MDO, and that’s the test for requiring a license.

Unexpected Microsoft Defender for Office 365 License Requirement for Shared Mailboxes

Posted on by Tony Redmond
Microsoft Defender for Office 365 Requires Licenses for Shared Mailboxes

A question about shared mailboxes brought up the topic of licensing requirements when a tenant has Microsoft Defender for Office 365 (MDO). The news is not good. Once MDO is active, every shared mailbox needs an MDO license, and every user mailbox must also be licensed for MDO (those with E5 licenses are covered). At $5 per month, those MDO licenses can ramp up to a considerable cost. Ouch!