Conversion of user mailboxes to shared mailboxes is common practice in many companies when employees leave.
Since the shared mailbox doesn’t require a license, it’s an easy and cheap way to “archive” the emails of former employees.
Quite often, companies perform additional steps as part of user decommissioning:
- Convert the user mailbox to a shared mailbox
- Hide the user from address lists
- Set up forwarding of emails to the user’s manager (or replacement)
- Configure manager (or replacement) access to the shared mailbox
- Remove the Exchange Online license
- Disable the AD account
All of these tasks typically involve multiple admin tools.
But let’s first look at the easiest way to do this!
Decommission a User With Mailbox Conversion, etc. – in 30 Seconds!
With Easy365Manager all of the above steps can be performed directly from AD Users & Computers in just 30 seconds.
Please watch us set a new world record performing a complete user decommissioning from a consolidated, intuitive graphical user interface:
Easy365Manager is a plug-in to AD Users & Computers that provides two new tabs in user properties.
With these two new tabs, you can literally cut away minutes from every time you retire a user account, configure calendar permissions, configure Outlook automapping, and much much more.
You’ll find an overview of all the great Easy365Manager features here.
Easy365Manager is available as a fully-functional 30-day trial here.
The trial doesn’t make any changes to your infrastructure or schema and you can remove it anytime using the .msi installer.
Decommission a User With Mailbox Conversion – Using the Standard Tools
Without Easy365Manager, you’re stuck with a broad range of tools to complete the above tasks:
- Exchange Online Admin Center (mailbox conversion, forwarding, delegation)
- Microsoft 365 Admin Center (license removal)
- Active Directory Users & Computers (account disabling)
- Exchange on-premises (hide from address lists)
- PowerShell (Azure AD Connect synchronization)
The complexity of this procedure (using the standard tools) can consume a lot of time from IT support.
Let’s have a look at the individual tasks.
Convert Mailbox in Exchange Admin Center
To convert a user mailbox to a shared mailbox, you need to navigate deep into the Exchange Online Admin Center:

Configure Mailbox Forwarding in Exchange Admin Center
You set up email forwarding to forward inbound emails to a manager or the replacement employee.
Like the mailbox conversion, this can be done via the Exchange Admin Center:

Configure Mailbox Delegation in Exchange Admin Center
To allow a manager or new employee to access the old mailbox, you need to delegate access.
Like the previous steps, this can be done via the Exchange Admin Center:

Configure Hide From Address Lists in Exchange On-Premises
On synchronized users, the Hide From Address Lists setting is authoritative in your on-premises Active Directory.
This is why (without Easy365Manager) you need to have an Exchange on-premises server to manage this.
Log in to your local Exchange on-premises server and go to properties of the user mailbox:

Configure Office 365 Licenses in Microsoft 365 Admin Center
To reclaim the Exchange Online license, you need another tool again: The Microsoft 365 Admin Center (or the Azure Portal).
This involves yet another logon and yet another drilling down to the object you need to configure:

Disable the AD User Account
Naturally, we want to disable the user’s account who left the company.
For this, you need to go to Active Directory Users & Computers and disable the account in the Account tab.
(this is now the fourth admin tool we have to visit):

Replicate On-Premises Changes to Azure AD
And finally, if you want to see the last two on-premises changes in Azure AD anytime soon, we need PowerShell.
Establish a remote connection with your Azure AD Connect Server and trigger a synchronization using the following commands:
PS C:\> Enter-PSSession DC-01 [DC-01]: PS C:\Users\Administrator.DC-01\Documents> Start-ADSyncSyncCycle -PolicyType Delta Result ------ Success [DC-01]: PS C:\Users\Administrator.DC-01\Documents> Exit-PSSession PS C:\>
How to Cut Your Admin Time in Half
As clearly illustrated in the above section, Easy365Manager can save you (or your first-level support) loads of time!
With Easy365Manager
- You manage AD and Office 365 in a single tool
- Office 365 management is super intuitive (building on the highly popular AD Users & Computers graphical user interface)
- You no longer need to worry about attribute authority (configure in AD or Office 365)
- You can remove Exchange on-premises (eliminate risk and cost)
Download the 30-day trial now and see how easy hybrid Office 365 management can be.
Easy365Manager only extends the functionality of the AD Users & Computers tool.
For technical details, have a look at the Installation and Configuration Guide.