Managing user lifecycle is a core responsibility for IT administrators, and one of the most common tasks during offboarding is handling the user’s mailbox. In Exchange Online, deleting a mailbox outright is rarely the best option. Emails often contain business-critical conversations, attachments, approvals, and historical references that teams may need even after an employee leaves.
This is where shared mailboxes become incredibly useful. By converting a user mailbox into a shared mailbox, organizations can preserve email data while eliminating the need for an active license. This approach ensures continuity without unnecessary cost, making it a standard best practice in most IT environments.
Convert a Regular Mailbox to a Shared Mailbox in Exchange Online
To convert a user mailbox to a shared mailbox in Exchange Online, you can use either the admin center or PowerShell. The user mailbox must have a license assigned to it before you begin the conversion, or the option to convert will not appear.
Method 1: Using the Exchange Admin Center (EAC)
This is the most straightforward graphical method.
- Log in to the Exchange Admin Center.
- Navigate to Recipients > Mailboxes.
- Select the user mailbox you want to convert.
- In the side pane, go to the Others tab and select Convert to shared mailbox.
- Click Confirm to complete the process.
Method 2: Using the Microsoft 365 Admin Center
Apart from Exchange admin center, you can also convert the user’s mailbox into shared mailbox in the Microsoft 365 admin center.
- Log in to the Microsoft 365 Admin Center.
- Go to Users > Active users.
- Select the specific user. On the Mail tab, select Convert to shared mailbox under More actions and then click Convert.
The admin centers are dependable and reasonably intuitive when handling single mailbox conversions. However, grouping this task under “Others” alongside unrelated settings like Custom Attributes and Automatic Replies isn’t exactly a great user experience.
For bulk operations, PowerShell is more efficient.
Method 3: Convert a User Mailbox to a Shared Mailbox Using PowerShell
Before starting, ensure that you have the Exchange Online PowerShell module installed and the necessary administrative permissions. Once connected, you can begin the conversion process.
Converting the Mailbox
The actual conversion is performed using a single command:
Set-Mailbox -Identity "formeruser@contoso.com" -Type Shared This command changes the mailbox type from a user mailbox to a shared mailbox while preserving all existing data. The process is typically quick and does not interrupt the mailbox content.
Verifying the Conversion
After executing the command, it is important to confirm that the conversion was successful.
Get-Mailbox -Identity "formeruser@contoso.com" | Select RecipientTypeDetails If the process was successful, the output should indicate that the mailbox is now a SharedMailbox. Verification is a crucial step before proceeding with license removal or account changes.
Granting Access to the Shared Mailbox
Once the mailbox has been converted, it does not automatically become accessible to others. Permissions must be explicitly assigned.
Add-MailboxPermission -Identity "formeruser@contoso.com" -User "manager@contoso.com" -AccessRights FullAccess -AutoMapping $trueNote: When AutoMapping is enabled, the shared mailbox automatically appears in the Outlook profile of every user who has Full Access, no manual configuration needed on their end. This is convenient for small teams but can clutter Outlook for large shared mailboxes. Set it to $false if you want users to add it manually in Outlook via File → Account Settings → More Settings. Unfortunately, you can only manage Outlook AutoMapping via PowerShell.
Disabling the User Account in Entra ID
Even after converting the mailbox, the associated user account in Microsoft Entra ID remains active unless explicitly disabled. This is a critical security consideration. Leaving the account active could allow unintended access if credentials are still valid.
Disabling the account ensures that the mailbox can be accessed only through assigned permissions and not through direct login.
Update-MgUser -UserId "formeruser@contoso.com" -AccountEnabled:$false Removing the License from the Converted Mailbox User
After converting the mailbox to a shared mailbox, you typically want to remove the assigned license to free up costs. Unlike mailbox conversion, this step cannot be performed using Exchange Online PowerShell. You need to connect to Microsoft Graph PowerShell.
Connect-MgGraph -Scopes "User.ReadWrite.All"To identify the correct SKU ID, you can run Get-MgSubscribedSku.
Set-MgUserLicense -UserId "formeruser@contoso.com" -RemoveLicenses @("ENTER-SKU-ID") -AddLicenses @{}Mailbox conversion is handled through Exchange Online PowerShell (EXO), while license removal requires the Microsoft Graph API. This forces administrators to switch tools and authenticate separately, adding unnecessary complexity.
Why EasyEntra Is the Better Way to Convert Mailboxes
While Microsoft’s native tools are powerful, they often require multiple steps across different interfaces. This can slow down helpdesk teams and introduce room for error.
EasyEntra simplifies this entire workflow by bringing mailbox management into a single, intuitive interface.
Instead of running scripts or navigating multiple admin portals, administrators can perform mailbox conversions directly from the mailbox properties view. The process becomes visual, fast, and accessible even to non-specialist staff.
Convert a Mailbox to Shared Mailbox Using EasyEntra
Follow these simple steps to convert a user mailbox into a shared mailbox directly from the EasyEntra interface:
- Navigate to the user in EasyEntra and open their Mailbox panel.
- Under the Type field, click the dropdown menu and select Shared mailbox. Mailbox types, including user, shared, room, and equipment, can be switched with just a few clicks, significantly reducing the operational burden.
- Click the button Mailbox Delegation to delegate full access to the mailbox.
- Go to the Account tab to disable the account.
- Click Apply (bottom-right corner) to save all changes in one go.
Additionally, you can assign mailbox delegation permissions on the same page to allow others to access the mailbox.
To remove the assigned license, navigate to the Licenses tab and uncheck the active license. Once done, click Apply to save the changes.
Unlike traditional methods in Exchange Online, this approach eliminates the need for PowerShell, avoids navigating multiple admin portals, and completes the entire task in just a few clicks.
