GROUP MODIFICATION DENIAL IN ADRESS BOOK

Dear @Hreinson, Katie (PacifiCorp),

Thank you for reaching out to Microsoft Q&A forum.

I understand that you're experiencing an unexpected issue with the Address Book in Outlook. Based on my research, this behavior occurs because being listed as an “Owner” of a distribution group in the Address Book does not always grant the full administrative authority required to modify it through the modern Outlook on the web interface. This typically happens due to organizational security policies or synchronization restrictions that override the local ownership status.

In other words, Outlook recognizes you as the owner, but the management path you’re using may be restricted by one of the following factors:

1. Use the Dedicated Group Management Portal

Microsoft has moved Distribution Group management out of the standard "Address Book" view in many versions of Outlook on the web. Instead of using the Address Book, try accessing the dedicated groups portal designed for end-users:

1. Navigate to the Exchange Group Management Portal. 
2. Click on the tab labeled Groups I own.
3. Select your group from the list. You should see an Edit or Manage Members option here. If you can edit the group here but not in the Address Book, it confirms the issue is with the Outlook web interface.

2.Verify the "MyDistributionGroups" Role (IT Admin Task)

If your group is cloud-based and the portal in Solution 1 still gives you an error, your organization may have a missing permission role in your user profile.

The issue likely lies in the Default Role Assignment Policy in Exchange. For owners to manage their own groups, IT must ensure the following role is enabled:

• Role Name: MyDistributionGroups
• Description: This role allows users to create and manage distribution groups they own.

For reference: Role assignment policies in Exchange Online | Microsoft Learn

Please contact your IT Administrator to confirm these settings. If you don't know who your IT administrator is, please refer to this article: How do I find my Microsoft 365 admin? - Microsoft Support 

For additional assistance, use this link to find the appropriate contact number: Global Customer Service phone numbers - Microsoft Support 
For further assistance, your IT Administrator may also submit a support ticket with Microsoft on your behalf.

I hope the information provided useful. I truly hope you get your issue resolved swiftly. Please know that even though I can't directly intervene, directing you to the correct, specialized support is the most effective help I can provide from my position. Thank you for your patience and understanding. I'm looking forward to your reply. 

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If you are the owner of a group in the Address Book and are unable to modify it, receiving an error message stating that you do not have the authority, this could be due to the group being hidden from the Global Address List (GAL). Owners of security groups cannot manage a group in the Exchange admin center if it is hidden from the GAL. To resolve this issue, you will need to unhide the group from the GAL.

Here are the steps you can take:

1. Unhide the Group: Ensure that the group is not hidden from the GAL. You may need to use PowerShell or consult your Exchange administrator to make this change.
2. Role Group Creation: If necessary, create a role group and assign the Distribution Group role to that role group. Add the users who need to manage groups that are hidden from the GAL to this role group.

By following these steps, you should be able to regain the ability to modify the group as needed.