Adding a Mailbox in Outlook on the Web While in your primary mailbox at https://outlook.office.com/mail/ hover your mouse over your email address towards the left side of the screen and click on the three dots next to it(visual example in screenshot of step 2). In the menu that pops up, click on the option "Add shared folder or mailbox". This will open a window for your Outlook settings automatically, which you can also navigate to manually by click the settings icon(gear) in the top right corner and go to "account" and "shared with me"Shortcut to the settings screen to add a shared mailbox In the settings screen that pops up there will be a text box you will need to click in and begin typing the mailbox you are wanting to add. For this example we're going to use the "WithU Document Review" mailbox. As you are typing either the name or the email address, once you see it populate under the text box you can then click on it to select it.Settings screen to add a shared mailbox with a dropdown example Once you have selected the email you are wanting to add, the continue button in the bottom will turn blue and you'll want to click that button. Outlook will possibly take a few seconds while it checks your permissions for that mailbox, but once it is done you should get a confirmation screen saying it has been added(see screenshot below). If you get an error or a screen that says you can not add that mailbox it is likely due to not having the correct permissions. If that is the case, reach out to a team lead to confirm whether or not you should have read permissions for that mailbox and if so they will either instruct you to contact IT or they will do so themselves.Confirmation screen that the mailbox has been added Once the mailbox has been successfully added you can find it by closing out the windows and viewing the left hand side of Outlook as seen below. Depending on how big you have your Outlook window, you may need to scroll down in order to see it. To view the mailbox you can click on the name and then "Inbox" or whichever section you are needing to view.Example of where to find the shared mailbox that was added