Microsoft 365 - Manage Full Mailbox, Send As, and Send on Behalf of Permissions

This document explains how to manage Full Mailbox, Send as, and Send on-behalf of permissions for a NetID, service account, and shared mailbox.

Important:

  • Administrative access: Permission to administer another account is required before access is available.
  • UW–Madison Microsoft 365 accounts only: Permissions only work between UW–Madison Microsoft 365 accounts. They cannot be assigned to external accounts (e.g., UW Health, Gmail, Yahoo).
  • Send As takes priority: If both Send As and Send on Behalf are granted, Send As takes priority.

Permission Types 

Permission Types

Permission

What It Allows

Example

Full Mailbox

Read, delete, create drafts, send calendar invites, create events.

Cannot send emails.

You can open and organize emails in another user’s mailbox, but you cannot send messages from it.

Send As

Send emails as the mailbox owner.

The “From” address shows the owner’s name.

You send an email from help@domain.wisc.edu, and recipients see it as coming directly from that address.

Send on Behalf

Send emails on behalf of the owner.

The “From” address shows “on behalf of.”

You send an email from help@domain.wisc.edu, and recipients see: “Bucky Badger on behalf of help@domain.wisc.edu.

Manage Mailbox Permissions for a NetID, Service Account, or Shared Mailbox

Account Permissions Page

The permissions page lets you add, remove, or fix a user’s mailbox permissions for a NetID, service account, or shared mailbox.

  • Permissions: Shows users who have full mailbox, send as, or send on-behalf of permissions.
  • Grant Permissions: Assigns full mailbox, send as, or send on-behalf of permissions.
  • Validate Mailbox Permissions: Verifies and fixes a user’s mailbox permission. 

    use report or fix permissions buttons

Manage Mailbox Permissions

As an authorized or domain administrator:

  1. Log in to the Wisc Account Administration site with your NetID credentials.

  2. Search for or select the account you want to manage.

  3. Click the Office 365 tab and select the Permissions option. 

  4. In the Permissions for field, enter the NetID of a valid UW-Madison Microsoft 365 account.

    enter/select the netid and desired permissions

  5.  Select the preferred Permission type (e.g., Send As, Send on Behalf, Full) and click Add Permission.

  1. If successful, the following message will appear:

    permissions successful message

     If unsuccessful, the following message will appear:

    permissions unsuccessful message

Note: If the process is unsuccessful or an error occurs, please contact the DoIT Help Desk.

Validate Mailbox Permissions

As an authorized or domain administrator:

  1. Log in to the Wisc Account Administration site with your NetID credentials.

  2. Search for or select the account you want to manage. 

    1. Missing an account: If you do not see the account you want to manage or you are logged directly into your NetID account, please review the following document: Wisc Account Administration Site - Logging In.

  3. Click the Office 365 tab and select the Permissions option. 

  4. Review existing permissions within the permissions table:

    use report or fix permissions buttons

Troubleshooting

  • Missing user: If a user is missing from the permissions table, you will need to reassign permissions using the "Manage Mailbox Permissions" section. 
  • Fix permissions: Validate or fix permissions using the buttons within the "Validate Mailbox Permissions" section.
  • Repair limitation: "Send on Behalf" of permissions cannot be repaired. You must remove and re-add this permission.


Keywords:
microsoft office365 o365 m365 delegates delegation assign grant management add remove tool linked reset validate validating fixing checking confirming repairing service account report user netid shared mailbox permissions send as on behalf administrative access 
Doc ID:
38816
Owned by:
O365 S. in Microsoft 365
Created:
2014-03-26
Updated:
2026-01-05
Sites:
DoIT Help Desk, Microsoft 365, Wisc Account Admin