Get-MailboxPermission

Syntax

Get-MailboxPermission
   [-Identity] <MailboxIdParameter>
   [-Owner]
   [-Credential <PSCredential>]
   [-DomainController <Fqdn>]
   [-GroupMailbox]
   [-ReadFromDomainController]
   [-ResultSize <Unlimited>]
   [-UseCustomRouting]
   [<CommonParameters>]

Get-MailboxPermission
   [-Identity] <MailboxIdParameter>
   [-User <SecurityPrincipalIdParameter>]
   [-SoftDeletedMailbox]
   [-Credential <PSCredential>]
   [-DomainController <Fqdn>]
   [-GroupMailbox]
   [-IncludeSoftDeletedUserPermissions]
   [-IncludeUnresolvedPermissions]
   [-ReadFromDomainController]
   [-ResultSize <Unlimited>]
   [-UseCustomRouting]
   [<CommonParameters>]

Description

The output of this cmdlet shows the following information:

• Identity: The mailbox in question.
• User: The security principal (user, security group, Exchange management role group, etc.) that has permission to the mailbox.
• AccessRights: The permission that the security principal has on the mailbox. The available values are ChangeOwner (change the owner of the mailbox), ChangePermission (change the permissions on the mailbox), DeleteItem (delete the mailbox), ExternalAccount (indicates the account isn't in the same domain), FullAccess (open the mailbox, access its contents, but can't send mail) and ReadPermission (read the permissions on the mailbox). Whether the permissions are allowed or denied is indicated in the Deny column.
• IsInherited: Whether the permission is inherited (True) or directly assigned to the mailbox (False). Permissions are inherited from the mailbox database and/or Active Directory. Typically, directly assigned permissions override inherited permissions.
• Deny: Whether the permission is allowed (False) or denied (True). Typically, deny permissions override allow permissions.

By default, the following permissions are assigned to user mailboxes:

• FullAccess and ReadPermission are directly assigned to NT AUTHORITY\SELF. This entry gives a user permission to their own mailbox.
• FullAccess is denied to Administrator, Domain Admins, Enterprise Admins and Organization Management. These inherited permissions prevent these users and group members from opening other users' mailboxes.
• ChangeOwner, ChangePermission, DeleteItem, and ReadPermission are allowed for Administrator, Domain Admins, Enterprise Admins and Organization Management. Note that these inherited permission entries also appear to allow FullAccess. However, these users and groups do not have FullAccess to the mailbox because the inherited Deny permission entries override the inherited Allow permission entries.
• FullAccess is inherited by NT AUTHORITY\SYSTEM and ReadPermission is inherited by NT AUTHORITY\NETWORK.
• FullAccess and ReadPermission are inherited by Exchange Servers, ChangeOwner, ChangePermission, DeleteItem, and ReadPermission are inherited by Exchange Trusted Subsystem and ReadPermission is inherited by Managed Availability Servers.

By default, other security groups and role groups inherit permissions to mailboxes based on their location (on-premises Exchange or Microsoft 365).

You need to be assigned permissions before you can run this cmdlet. Although this topic lists all parameters for the cmdlet, you may not have access to some parameters if they're not included in the permissions assigned to you. To find the permissions required to run any cmdlet or parameter in your organization, see Find the permissions required to run any Exchange cmdlet.

Examples

Example 1

Get-MailboxPermission -Identity [email protected] | Format-List

This example returns permissions on the mailbox by its SMTP address [email protected].

Example 2

Get-MailboxPermission -Identity [email protected] -User "Ayla"

This example returns permissions that the user Ayla has on John's mailbox.

Example 3

Get-MailboxPermission -Identity Room222 -Owner

This example returns the owner information for the resource mailbox Room222.

Parameters

-Credential

-DomainController

-GroupMailbox

-Identity

-IncludeSoftDeletedUserPermissions

-IncludeUnresolvedPermissions

-Owner

-ReadFromDomainController

-ResultSize

-SoftDeletedMailbox

-UseCustomRouting

-User

Inputs

Input types

To see the input types that this cmdlet accepts, see Cmdlet Input and Output Types. If the Input Type field for a cmdlet is blank, the cmdlet doesn't accept input data.

Outputs

Output types

To see the return types, which are also known as output types, that this cmdlet accepts, see Cmdlet Input and Output Types. If the Output Type field is blank, the cmdlet doesn't return data.