If you have access to a shared mailbox in Office 365, by default the mailbox will show up in your Outlook account. This is how to stop a shared mailbox from automapping in your Outlook client

Open up Windows Powershell on your computer, which is preloaded on Windows computers
Copy and paste this command into your Powershell application to login to Office 365
Connect-ExchangeOnline
Run this command so that Powershell will understand your Office 365 commands
Import-Module ExchangeOnlineManagement
Run this command to remove AutoMapping of a shared mailbox to your Outlook profile
Add-MailboxPermission -Identity kathleenr@contoso.onmicrosoft.com -User admin@contoso.onmicrosoft.com -AccessRights FullAccess -AutoMapping $false
- For the Identity email address enter the mailbox of the person with the Outlook profile
- For User enter the shared mailbox account you want removed from Outlook
What you have done in this article is:
- Used PowerShell to access Office 365’s backend, and install the Exchange Module so that it understands your commands
- Ran a command to set AutoMapping in Outlook to $False (i.e., turned it off)
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This fix is part of our full Microsoft 365 & Outlook Troubleshooting Guide.
See the Full Guide

