Mailbox helpers

Requires an EXO session. For full details and examples, run Get-Help <FunctionName> -Detailed.

Add-MboxAlias

Add SMTP aliases on a recipient.

Syntax

Add-MboxAlias -SourceMailbox <String> -MailboxAlias <String>

Parameter	Type	Description	Required	Default
SourceMailbox (Identity)	String	Target mailbox/recipient. Pipeline accepted.	Yes	-
MailboxAlias	String	Alias (SMTP address) to add.	Yes	-

Examples

Add-MboxAlias -SourceMailbox 'user@contoso.com' -MailboxAlias 'alias@contoso.com'

Add-MboxAlias -Identity 'user@contoso.com' -MailboxAlias 'alias@contoso.com'

Add-MboxPermission

Grant mailbox permissions.

Syntax

Add-MboxPermission -SourceMailbox <String> -UserMailbox <String[]> [-AccessRights <String>] [-AutoMapping] [-PassThru]

Parameter	Type	Description	Required	Default
SourceMailbox (Identity)	String	Target mailbox.	Yes	-
UserMailbox	String[]	One or more principals to grant. Pipeline accepted.	Yes	-
AccessRights	String	Rights: All, FullAccess, SendAs, SendOnBehalfTo.	No	All
AutoMapping	Switch	Enable/disable Outlook automapping.	No	False
PassThru	Switch	Emit detailed permission objects (default shows only confirmation messages).	No	False

Examples

Add-MboxPermission -SourceMailbox 'sharedmailbox@contoso.com' -UserMailbox 'user@contoso.com' -AccessRights FullAccess -AutoMapping:$false

Add-MboxPermission -SourceMailbox 'sharedmailbox@contoso.com' -UserMailbox 'user@contoso.com' -PassThru

Export-MboxPermission

Export mailbox permissions to CSV with optional batching and resume support.

Syntax

Export-MboxPermission -RecipientType <String> [-CsvFolder <String>] [-BatchSize <Int32>] [-Resume] [-CsvPath <String>] [-MaxConsecutiveErrors <Int32>]

Parameter	Type	Description	Required	Default
RecipientType	String	Recipient type to analyze: User, Shared, Room, or All.	Yes	-
CsvFolder	String	Destination folder for the CSV.	No	Current directory
BatchSize	Int32	Number of processed mailboxes buffered before the CSV is flushed.	No	25
Resume	Switch	Resume from the latest matching CSV or from -CsvPath.	No	False
CsvPath	String	Explicit CSV file to resume. When omitted, the latest matching CSV is used.	No	-
MaxConsecutiveErrors	Int32	Stop after this many consecutive mailbox-level failures.	No	5

Examples

Export-MboxPermission -RecipientType All -CsvFolder 'C:\Temp' -Resume

Export-MboxPermission -RecipientType Shared -CsvFolder 'C:\Temp' -CsvPath 'C:\Temp\20260414_M365-MboxPermissions-Report.csv'

Export-MboxAlias

:::warning Deprecated function Export-MboxAlias is deprecated and no longer available as a function. Use Get-MboxAlias instead. :::

Get-MboxAlias

List aliases for auditing. This also replaces Export-MboxAlias.

Get-MboxAlias is now the single command for alias reporting. It supports:

• a single mailbox or recipient identity
• tenant-wide export with -All
• domain-scoped export with -Domain
• CSV output for single mailbox queries with -Csv and -CsvFolder
• automatic CSV export for -All and -Domain
• batch flushing and resume for long-running CSV exports with -BatchSize, -Resume, -CsvPath, and -MaxConsecutiveErrors
• optional inclusion of primary-only recipients with -IncludePrimaryOnly
• extra CSV fields DisplayName and Name
• extra CSV fields UserPrincipalName and IsMoera in CSV exports

Note:

• -Csv is the explicit switch for single-mailbox exports.
• -All and -Domain already export to CSV, so -Csv is optional in those modes.
• -CsvFolder controls the export destination for every CSV-producing mode.
• -Resume reuses the latest matching CSV in the target folder unless -CsvPath is specified.
• -BatchSize controls how many processed recipients are buffered before the CSV is flushed.
• -IncludePrimaryOnly keeps recipients that would otherwise be omitted because they have no secondary aliases.
• -IncludeMoera keeps addresses in the tenant's onmicrosoft.com domain that would otherwise be hidden.
• Primary-only exclusion is evaluated after MOERA filtering, so a mailbox with only a primary SMTP and a MOERA proxy stays hidden by default.

Syntax

Get-MboxAlias -SourceMailbox <String> [-Csv] [-CsvFolder <String>] [-IncludePrimaryOnly] [-IncludeMoera] [-BatchSize <Int32>] [-Resume] [-CsvPath <String>] [-MaxConsecutiveErrors <Int32>] [-All] [-Domain <String>]

Parameter	Type	Description	Required	Default
SourceMailbox (Identity)	String	Target mailbox/recipient. Pipeline accepted.	Yes in single mode	-
Csv	Switch	Force CSV export for a single mailbox query. Optional when using -All or -Domain.	No	False
CsvFolder	String	Destination folder for CSV export.	No	-
IncludePrimaryOnly	Switch	Include recipients with only a primary SMTP address in CSV exports.	No	False
IncludeMoera	Switch	Include MOERA addresses in CSV exports.	No	False
BatchSize	Int32	Number of processed recipients to buffer before flushing the CSV.	No	25
Resume	Switch	Resume from the latest matching CSV or from -CsvPath.	No	False
CsvPath	String	Explicit CSV file to resume. When omitted, the latest matching CSV is used.	No	-
MaxConsecutiveErrors	Int32	Stop after this many consecutive recipient-level failures.	No	5
All	Switch	Export aliases for all non-guest recipients and write a CSV report.	No	False
Domain	String	Export aliases for recipients matching a domain and write a CSV report.	No	-

Examples

Get-MboxAlias -SourceMailbox 'user@contoso.com'

Get-MboxAlias 'user@contoso.com'

Get-MboxAlias -SourceMailbox 'user@contoso.com' -Csv -CsvFolder 'C:\Temp'

Get-MboxAlias -SourceMailbox 'user@contoso.com' -Csv -IncludePrimaryOnly -CsvFolder 'C:\Temp'

Get-MboxAlias -SourceMailbox 'user@contoso.com' -Csv -IncludeMoera -CsvFolder 'C:\Temp'

Example behavior:

• Get-MboxAlias -SourceMailbox 'user@contoso.com' -Csv hides the MOERA row and keeps the mailbox only if it has a real secondary alias.
• Get-MboxAlias -SourceMailbox 'user@contoso.com' -Csv -IncludeMoera includes the MOERA row as well.

Get-MboxAlias -All -CsvFolder 'C:\Temp'

Get-MboxAlias -Domain 'contoso.com' -CsvFolder 'C:\Temp'

Get-MboxAlias -All -CsvFolder 'C:\Temp' -Resume

Get-MboxAlias -Domain 'contoso.com' -CsvFolder 'C:\Temp' -Resume -CsvPath 'C:\Temp\20260414_M365-Alias-Report.csv'

Get-MboxLastMessageTrace

Return the most recent received and sent message traces for a mailbox.

Syntax

Get-MboxLastMessageTrace -SourceMailbox <String> [-IncludeTrace]

Parameter	Type	Description	Required	Default
SourceMailbox (Identity)	String	Target mailbox/recipient. Pipeline accepted.	No	-
IncludeTrace	Switch	Include raw message trace objects in the output.	No	False

Example

Get-MboxLastMessageTrace -SourceMailbox 'user@contoso.com'

Get-MboxLastMessageTrace -SourceMailbox 'user@contoso.com' -IncludeTrace

Get-MboxPermission

List mailbox permissions.

Syntax

Get-MboxPermission -Identity <String>

Parameter	Type	Description	Required	Default
Identity	String	Target mailbox.	Yes	-

Examples

Get-MboxPermission -Identity 'sharedmailbox@contoso.com'

Get-MboxPrimarySmtpAddress

Return the PrimarySmtpAddress for a mailbox or recipient.

Syntax

Get-MboxPrimarySmtpAddress -SourceMailbox <String[]> [-Raw] [-Detailed]

Parameter	Type	Description	Required	Default
SourceMailbox (Identity)	String[]	Target mailbox/recipient. Pipeline accepted.	Yes	-
Raw	Switch	Return only the PrimarySmtpAddress values.	No	False
Detailed	Switch	Include additional fields (Identity, RecipientTypeDetails).	No	False

tip

Get-MboxPrimarySmtpAddress is also available as gpa (alias).

By default, object output is compact and optimized for console readability:

• DisplayName
• PrimarySmtpAddress

Example

Get-MboxPrimarySmtpAddress -SourceMailbox 'user@contoso.com'

Get-MboxPrimarySmtpAddress -SourceMailbox 'user@contoso.com' -Raw

gpa 'user@contoso.com' -Raw

Get-MboxPrimarySmtpAddress -SourceMailbox 'user@contoso.com' -Detailed

Get-UserLastSeen

Return the most recent activity for a mailbox combining Exchange LastUserActionTime and (when available) Entra ID sign-in logs.

Syntax

Get-UserLastSeen -User <String>

Parameter	Type	Description	Required	Default
User (Identity, UserPrincipalName)	String	Target mailbox identity. Pipeline accepted.	No	-

Example

Get-UserLastSeen -User 'user@contoso.com'

Notes:

• Requires Exchange Online connection. Graph sign-in logs are included when AuditLog.Read.All + Directory.Read.All scopes are available.
• Output includes LastUserActionTime, LastInteractiveSignIn, LastSeen, and the Source used.

New-SharedMailbox

Create a shared mailbox.

Syntax

New-SharedMailbox -SharedMailboxSMTPAddress <String> -SharedMailboxDisplayName <String> -SharedMailboxAlias <String>

Parameter	Type	Description	Required	Default
SharedMailboxSMTPAddress	String	Primary SMTP address of the new shared mailbox.	Yes	-
SharedMailboxDisplayName	String	Display name.	Yes	-
SharedMailboxAlias	String	Mail alias.	Yes	-

Example

New-SharedMailbox -SharedMailboxSMTPAddress 'sharedmailbox@contoso.com' -SharedMailboxDisplayName 'Support Team' -SharedMailboxAlias 'SupportTeam'

Remove-MboxAlias

Remove SMTP aliases from a recipient.

Syntax

Remove-MboxAlias -SourceMailbox <String> -MailboxAlias <String>

Parameter	Type	Description	Required	Default
SourceMailbox (Identity)	String	Target mailbox/recipient. Pipeline accepted.	Yes	-
MailboxAlias	String	Alias (SMTP address) to remove.	Yes	-

Examples

Remove-MboxAlias -SourceMailbox 'user@contoso.com' -MailboxAlias 'alias@contoso.com'

Remove-MboxPermission

Revoke mailbox permissions.

Syntax

Remove-MboxPermission -SourceMailbox <String> -UserMailbox <String[]> [-AccessRights <String>]
Remove-MboxPermission -SourceMailbox <String> -ClearAll
Remove-MboxPermission <SourceMailbox> <UserMailbox> [-AccessRights <String>]

Parameter	Type	Description	Required	Default
SourceMailbox (Identity)	String	Target mailbox.	Yes	-
UserMailbox	String[]	Principal(s) to revoke.	Yes (User mode)	-
AccessRights	String	Rights (e.g., FullAccess, SendAs, SendOnBehalfTo). Defaults to All.	No	All
ClearAll	Switch	Remove all non-inherited FullAccess, SendAs, and SendOnBehalfTo permissions from the source mailbox.	Yes (All mode)	-

Examples

Remove-MboxPermission -SourceMailbox 'sharedmailbox@contoso.com' -UserMailbox 'user@contoso.com' -AccessRights FullAccess

# Positional call (SourceMailbox = position 0, UserMailbox = position 1)
Remove-MboxPermission 'sharedmailbox@contoso.com' 'user@contoso.com'

Remove-MboxPermission -SourceMailbox 'sharedmailbox@contoso.com' -ClearAll

Set-MboxLanguage

Set mailbox UI language and regional defaults.

Syntax

Set-MboxLanguage -SourceMailbox <String[]> [-Language <String>]
Set-MboxLanguage -Csv <String> [-Language <String>]

Parameter	Type	Description	Required	Default
SourceMailbox (Identity)	String[]	Target mailbox(es). Pipeline accepted.	No	-
Csv	String	CSV file path containing EmailAddress column.	No	-
Language	String	Culture code (e.g., it-IT, en-US).	No	it-IT

Example

Set-MboxLanguage -SourceMailbox 'user@contoso.com' -Language it-IT

Set-MboxLanguage -Csv 'C:\Temp\mailboxes.csv' -Language en-US

Set-MboxRulesQuota

Set rules quota to 256KB for one or more mailboxes.

Syntax

Set-MboxRulesQuota -SourceMailbox <String[]>

Parameter	Type	Description	Required	Default
SourceMailbox (Identity)	String[]	Target mailbox(es). Pipeline accepted.	No	-

Example

Set-MboxRulesQuota -SourceMailbox 'user@contoso.com','sharedmailbox@contoso.com'

Set-SharedMboxCopyForSent

Enable sent-item copy settings for shared mailboxes.

Syntax

Set-SharedMboxCopyForSent -SourceMailbox <String[]>

Parameter	Type	Description	Required	Default
SourceMailbox (Identity)	String[]	Shared mailbox(es). Pipeline accepted.	Yes	-

Example

Set-SharedMboxCopyForSent -SourceMailbox 'sharedmailbox@contoso.com'

Test-SharedMailboxCompliance

Report shared mailbox sign-in activity and Exchange Online licensing indicators.

Syntax

Test-SharedMailboxCompliance [-GridView]

Parameter	Type	Description	Required	Default
GridView	Switch	Show output in Out-GridView (default behavior). Use -GridView:$false to return objects.	No	True

Example

Test-SharedMailboxCompliance