Convert User Mailbox to Resource Mailbox in Exchange Online

Step-by-step documentation for converting a user mailbox to a resource mailbox in Exchange Online using PowerShell.

Prerequisites

1. Ensure you are connected to Exchange Online PowerShell:

   Connect-ExchangeOnline

2. You must have appropriate Exchange administrator rights.

Verifying the Mailbox

Make sure the mailbox exists and is of type UserMailbox:

Get-Mailbox -Identity user@example.com | Format-List Name,RecipientTypeDetails

Conversion Command (Correct Approach in Exchange Online)

Use Set-Mailbox to convert a user mailbox to a room or equipment mailbox.

Convert to Room Mailbox

Set-Mailbox -Identity user@example.com -Type Room

Convert to Equipment Mailbox

Set-Mailbox -Identity user@example.com -Type Equipment

Verifying the Conversion

After running the conversion command, check the mailbox type with:

Get-Mailbox -Identity user@example.com | Format-List Name,RecipientTypeDetails

You should now see:

• RecipientTypeDetails: RoomMailbox or
• RecipientTypeDetails: EquipmentMailbox

Important Notes

• This method does not delete or disable the mailbox.
• The mailbox type is reclassified, preserving all data and access.
• The Enable-Mailbox -Room and Enable-Mailbox -Equipment parameters are not valid in Exchange Online and will throw a ParameterBindingException.

Summary