Join a group in Outlook on the Web
Applies to: Outlook on the web (OWA)
When you join a group, you gain access to the group mailbox, calendar, OneNote notebook, and team site. Permissions are taken care of automatically so you don't need to worry about missing any of the meetings or conversations.
Join a group
1. Open Outlook on the web.
2. In the navigation pane, under Groups, select Discover. (If you don't see Discover, click More at the bottom of your groups list. Once all of your groups are displayed you should see the Discover link.)
3. All available groups will be listed in alphabetical order. Select the one you want and click Join. If the group is public, you'll see a confirmation message and become a member right away. If the group is private, type a reason why you want to join > Send.
Tips: How do you know at a glance whether a group is private? Sometimes it's noted at the top of the group card, as in this example.
Once you've joined a group you'll receive a welcome message that contains important information and links to help you get started. If the group is public, you'll get the message right away. If the group is private, you'll get the welcome message after you've been approved by group owner.
1. Open Outlook on the web.
2. In the navigation pane, next to Groups, select the + button. (If you don't see the + button, hover your mouse over the navigation pane.)
3. In Choose a name, enter a group name that briefly captures the spirit of the group.
4. A suggested group ID is provided. To assign a different name to your group which will be part of the group URL, click Edit 
next to the Group ID box.
If you see "not available," the group ID is already in use. Try something different. Note that once you choose a group ID, it cannot be changed.
5. In Add a description, enter a detailed description of the group to help others understand its purpose. This description will be included in the welcome email when others join the group.
6. In Privacy, do one of the following:
o To create a group in which anyone within your organization can view its content and become a member, select Public.
o To create a group in which membership requires approval by a group owner and only members can view group content, select Private.
7. To enable subscribed members to receive email and calendar event notifications in both their group inbox and personal inbox, select Subscribe members so they receive group conversations and calendar events in their inbox. This is recommended when members belong to multiple groups because it means they can see all group notifications in one place without having to visit each group mailbox in order to stay current with group activity.
8. Select Create.
9. If you're ready to add members to your newly created group (you aren't able to add external users at this time), continue with the create group wizard. Otherwise, select Not now. You can always come back and add group members later
Subscribe and Unscribe from mail
Once you have navigated to your Group within Outlook for Office 365, click on the link Joined next to the icons of the group members. If the option states “Unsubscribe from email for this group”, then you are subscribed and you will receive mail as members send it from the group.
If you no longer wish to recieve mail, you can click ont he Unsubscribe and you will stop recieving mail from the group.
Private groups vs public groups
When creating a group, you'll need to decide if you want it to be a private group or a public group. Content in a public group can be seen by anybody in your organization, and anybody in your organization is able to join the group. Content in a private group can only be seen by the members of the group and people who want to join a private group have to be approved by a group owner.
Neither public groups nor private groups can be seen or accessed by people outside of your organization unless those people have been specifically invited as guests.