Microsoft 365 - Mail and Calendar folder permission levels
By default, no one has any permissions to access/view your emails and only has free/busy lookup for your calendar. If another person needs more permissions then the default, you will need to grant them those permissions. Below lists all the permissions levels you can manage.
Important: The office 365 team recommends that you use Outlook on the web to manage permissions - this ensures permissions are more predictable and lessons the chance of conflicts. This also allows for simpler troubleshooting, should it be necessary.
Calendar permission levels
Outlook on the web, Outlook 365 Enterprise/Subscription Windows/MacOS clients
Can view when I'm busy: Allows someone to view blocks of time as Free, Busy, Tentative, Away.
Can view titles and locations: Allows someone to view your Subject and Location. Events set to private will only display as Private Appointment.
Can view all details: Allows someone to view your Subject, Location, Attendees, and Description. However, any event you mark as private displays simply as Private Appointment.
Can edit: Provides read/write/modify access.
Delegate: In addition to "Editor" permissions, a delegate can also be selected to receive calendar notifications/requests/invitations. By default, 'Delegates' cannot view/modify events set to Private. You do have the option to grant the delegate the ability to view (full details) Private events. A delegate will not receive calendar notifications/requests/invitations that are set as private - they will need to open the calendar of the user who they are a delegate for and taken action on the specific event - learn more.
Outlook 2016 for Windows/MacOS clients
None: User will be unable to view any information (including free/busy times).
Free/Busy time: Allows someone to view blocks of time as Free, Busy, Tentative, Away.
Free/Busy time, subject, location: Allows someone to view your Subject and Location. Events set to private will only display as Private Appointment.
Contributor: Provides the ability to view free/busy information and create new events.
Reviewer: Allows someone to view your Subject, Location, Attendees, and Description. However, any event you mark as private displays simply as Private Appointment.
Nonediting Author: Provides the ability to view full details of all events (accept private ones), create new events, and delete events they have created.
Author: In addition to permissions granted via "Nonediting Authour", the user will also me able to edit events they have created.
Publishing Author: In addition to permissions granted via "Authour", the user will also me able to create sub-folders (these are calendar groups or secondary calendars).
Editor: Provides read/write/modify access to the calendar (accept private events).
Publishing Editor: In addition to "Editor" permissions, the user will also be able to create sub-folders (these are calendar groups or secondary calendars).
Owner: In addition to "Editor" permissions, an owner (delegate) can also be selected to receive calendar notifications/requests/invitations. By default, 'Delegates' cannot view/modify events set to Private. You do have the option to grant the delegate the ability to view (full details) Private events. A delegate will not receive calendar notifications/requests/invitations that are set as private - they will need to open the calendar of the user who they are a delegate for and taken action on the specific event - learn more.
Known issue:
Occasionally a user is unable to open your calendar or work as the permissions you have granted them after you share it. In some occasions, resetting the permissions using the email address of the person you are sharing with may solve the issue.
Sometimes, the following workaround works:
- Unsubscribe from the calendar from Outlook on the web and Outlook desktop client.
- Ask the owner of the calendar to remove the user from the permissions listing.
- Wait 30-60 minutes for this change to be synced.
- Add the user again using Outlook on the web, but this time add them by using their email address to look them up. Make sure to select "Use this address:..." option.
- Wait 30-60 minutes for this change to be synced.
- Ask the user to subscribe to the calendar via Outlook on the web - they should have received an email notification - and verify if they can interact with the calendar per the granted permissions.
Mail permission levels
Outlook on the web and Outlook for Windows/MacOS clients
Owner: Create, read, modify, and delete all items and files, and create sub-folders. As the folder owner, you can change the permission levels others have for the folder. (Does not apply to delegates.)
None: You have no permission. You cant open the folder.
Contributor: Create items and files only. The contents of the folder do not appear. (Does not apply to delegates.)
Reviewer: Read items and files only.
Non-Editing Author: Full read details. Create items. Delete own items. Folder visible.
Publishing Editor: Create, read, modify, and delete all items and files, and create sub-folders. (Does not apply to delegates.)
Editor: Create, read, modify, and delete all items and files.
Publishing Author: Create and read items and files, create sub-folders, and modify and delete items and files you create. (Does not apply to delegates.)
Author: Create and read items and files, and modify and delete items and files you create.
Custom: Perform activities defined by the folder owner. (Does not apply to delegates.)
Note - With author or editor permissions, a delegate has send-on-behalf-of permission. Sent messages contain both the managers and delegates names. Message recipients see the managers name in the Sent On Behalf Of box and the delegates name in the From box.