Alan here, this guide only applies to the outlook web app as the windows 10 app will do all this automatically. Remember, it takes around 60 minutes for the shared mailbox to propagate.
there are two ways to make a shared mailbox. The most common way is to make a shared mailbox, the other is to share a users mailbox. For examples, we will be following on from my sharing a users mailbox guide where I share Joe’s mailbox so I can read and manage his mailbox. This guide will apply for new shared mailboxes too.
Once the hour has passed after clicking save changes, we need to right click on the folders tab inside the mailbox you want to share to.
In the right click menu, click add shared folder.
Type the email address in the textbox that pops up. Often it can autocomplete the address for you.
After the correct user is selected, click add.
The new inbox will show in the left menu and can be accessed like any other folder.
All done. I can now freely access and manage joe’s emails but he cant see mine.