converting a shared Mailbox - is the user sent a message?

Question

We are offboarding some employees. We believe we have the steps down - but are wondering if we convert the mailboxes early to "shared Mailboxes" we can eliminate a step after the offboarding meeting and go right to signing them out, and changing passwords. Does the USER we convert receive or know IN ANY WAY that their mailbox has been converted to a SHARED mailbox? Are they sent a notification?

Thanks -

Kathy

Answer 1

Hi @Kathy Rivers,  

Welcome to the Microsoft Q&A forum. 

Regarding your inquiry about converting user mailboxes to shared mailboxes, please be advised that Microsoft does not send automated notifications to the end-user during this process. The transition occurs on the backend and is generally transparent within the Outlook interface while a session is active. 

While the conversion is silent, certain secondary actions may alert the user: 

• Credential prompts: If the account password is changed simultaneously with the conversion, the user will be prompted to re-authenticate, indicating a lockout. 
• Sync disruption: Mobile applications (Outlook for iOS/Android) are more sensitive to backend changes and may occasionally report sync errors shortly after the transition. 

This article provides additional details regarding your inquiry: Convert a user mailbox to a shared mailbox - Microsoft 365 admin | Microsoft Learn 

To maintain discretion until the offboarding meeting, I recommend the following workflow: 

1. Convert to shared mailbox: This is a background task that does not interrupt the user's active session. 
2. Assign permissions: Grant "Full Access" and "Send As" permissions to the designated manager or successor; this step is also silent. 
3. Execute final actions: Once the offboarding meeting has commenced, perform the more visible steps: 

• Initiate a Global Sign-out via the Admin Center and update the account password. 
• Remove the Microsoft 365 license. As a shared mailbox, the data remains accessible without a paid license, provided the mailbox size is under 50GB. 

This approach ensures a seamless transition while maintaining administrative control. Please feel free to reply if you have any further questions; I would be happy to assist further.

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Answer 2

Converting a user mailbox to a shared mailbox does not send any automatic notification or alert to the user whose mailbox is being converted.

Key behaviors from the documented process:

• Conversion is done by an admin in the Microsoft 365 admin center or Exchange admin center.
• The mailbox contents (mail, calendar) are retained and become accessible as a shared mailbox.
• There is no documented user-facing notification or email generated by Microsoft 365/Exchange as part of the conversion.
• After conversion, the account can have its license removed (if under 50 GB) and sign-in can be blocked as part of offboarding, but those are separate admin actions.

So, if the mailbox is converted to a shared mailbox before the offboarding meeting, the user is not automatically informed of that change by the system.

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References:

• Convert a user mailbox to a shared mailbox
• About shared mailboxes in Microsoft 365
• Step 4 - Forward a former employee's email to another employee or convert to a shared mailbox
• Convert a mailbox in Exchange Online
• Shared mailboxes in Exchange Server
• Shared mailboxes