If you need to edit the rules for a shared mailbox, the shared mailbox must be added to your Outlook Client account in a specific way. This article lists the steps to add the mailbox and then access the rules.

Add Mailbox

Open Outlook and traverse to File > Account Settings > Account Settings.
On the Email tab, select New and then enter the information for the shared mailbox and click Next.
1. Please note, for the password you must enter the password for your OWN mailbox.
After Outlook has searched for and found the shared mailbox, another login screen will appear. You'll notice that this is already set for the shared mailbox. Select the 'Sign in with another account' option.
Select YOUR email account and enter YOUR password when prompted.
After you have been successfully authenticated into the mailbox, click Finish on the Add Account screen.
Close the Account Settings screen and restart Outlook.
The shared mailbox will now appear on the left side of Outlook Client.

Edit Rules

Click on the shared mailbox.
In the Home ribbon, click the arrow below Rules and select Manage Rules & Alerts.
The rules displayed now should be those for the shared mailbox rather than your own account.
If you need assistance modifying a rule, please read Create a Rule in Outlook 2016.

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