Exchange Online PowerShell commands cheat sheet

Install the Exchange Online PowerShell module from the PowerShell Gallery.

Versions 3.10.0 and later need PowerShell 7.6 or later on PowerShell 7; Windows PowerShell 5.1 is not affected.

Update an existing installation to the latest release.

Load the module into the current session.

Usually optional: running Connect-ExchangeOnline loads an installed module for you.

Sign in to Exchange Online PowerShell with modern authentication, with or without MFA.

Add -Device on a machine without a browser, or -DelegatedOrganization <tenant>.onmicrosoft.com to manage a customer tenant as a partner.

List the active REST-based connections in this PowerShell window.

Get-PSSession does not show REST connections, so use this instead.

Close the session without a confirmation prompt.

Always disconnect when finished; abandoned sessions count against your limit until they expire.

List every mailbox with a minimal, fast set of properties.

The default is 1000 results. Add -Properties or -PropertySets (for example Quota, Archive, Delivery) for more fields.

List mailboxes of one subtype, such as shared or room mailboxes.

Show chosen properties for one mailbox.

Show the full property set for a mailbox, including properties Get-EXOMailbox leaves out.

Slower than Get-EXOMailbox for bulk queries; use it for single mailboxes.

Show mailbox size, item count and deleted item size.

Add -Archive to get the same figures for the archive mailbox.

Create a shared mailbox.

Convert a user mailbox to a shared mailbox.

Use -Type Regular to convert back. Other values: Room, Equipment.

Add a secondary SMTP address without touching existing addresses.

Use @{Remove="<address>"} to remove one. Listing addresses without Add or Remove replaces them all.

Hide a mailbox from the global address list.

Give a user full access to open another mailbox.

-AutoMapping $false stops Outlook adding the mailbox automatically. The default is $true.

List who has permissions on a mailbox.

Take away a user's full access to a mailbox.

Warning: Warning: the user loses access to the mailbox immediately. Confirm the user and mailbox before running it.

Let a user send mail that appears to come directly from the mailbox.

List Send As permissions on a mailbox.

Remove a user's Send As permission.

Warning: Warning: the user can no longer send as the mailbox. Confirm the trustee first.

Let a user send on behalf of the mailbox without replacing existing delegates.

Recipients see "<sender> on behalf of <mailbox>". Without @{Add=...} the list is overwritten.

Forward a mailbox's mail to another address and keep a copy in the mailbox.

With -DeliverToMailboxAndForward $false (the default) mail is only forwarded, not kept.

Turn off SMTP forwarding on a mailbox.

Audit forwarding settings across all mailboxes.

The Delivery property set includes ForwardingAddress, ForwardingSmtpAddress and DeliverToMailboxAndForward.

List a mailbox's Inbox rules.

-IncludeHidden also returns hidden rules. Filtering on ForwardTo, ForwardAsAttachmentTo and RedirectTo finds rules that send mail elsewhere, a common sign of a compromised account.

Delete an Inbox rule from a mailbox.

Warning: Warning: the rule is deleted permanently. Piping Get-InboxRule into Remove-InboxRule removes every rule in the mailbox.

Trace messages from a sender over a date range.

Replaces Get-MessageTrace, which Microsoft is deprecating. Searches the last 90 days, at most 10 days per query; returns 1000 results by default and up to 5000 with -ResultSize. Dates use your computer's short date format.

Find messages to a recipient that failed delivery.

Without dates it covers the last 48 hours. Other -Status values: Delivered, Expanded, FilteredAsSpam, GettingStatus, Pending.

Show the event-by-event detail of one traced message.

List mail flow (transport) rules.

Create a mail flow rule that tags the subject of mail from outside the organisation.

Add -Mode Audit to log what the rule would do without changing messages. Enforce is the default.

List the domains the tenant accepts mail for; also a quick test that you are connected.

Turn on the archive mailbox for an existing mailbox.

List only mailboxes that have an archive enabled.

Assign a messaging records management (MRM) retention policy to a mailbox.

Ask the Managed Folder Assistant to process a mailbox's retention settings now.

Useful after enabling an archive or changing a retention policy instead of waiting for the next scheduled run.

Place a mailbox on Litigation Hold so deleted and changed items are kept.

-LitigationHoldDuration is in days from when each item was received or created; the default is unlimited.

List distribution groups and mail-enabled security groups.

Create a distribution group with initial members.

Add -Type Security to create a mail-enabled security group instead.

List the members of a distribution group.

Add a member to a distribution group.

Remove a member from a distribution group.

Warning: Warning: the member stops receiving the group's mail and loses any access granted through the group.

List Microsoft 365 groups.

The example finds groups with no owner.

List the members (or owners) of a Microsoft 365 group.

Add members (or owners) to a Microsoft 365 group.

With this cmdlet a user must be a member before you can add them with -LinkType Owners.

Share a calendar with a user at a given permission level.

Common roles: AvailabilityOnly, LimitedDetails, Reviewer, Editor, Owner. -SharingPermissionFlags Delegate makes the user a calendar delegate.

List who has access to a calendar and at what level.

Change an existing calendar permission.

Set- modifies an existing permission entry; use Add- for a user who has no entry yet.

Remove a user's access to a calendar.

Warning: Warning: the user immediately loses the calendar, including any delegate rights.

Make a room or equipment mailbox accept or decline bookings automatically.

None disables processing; AutoUpdate leaves requests tentative until a delegate approves.

Show a resource mailbox's booking settings.

Schedule out-of-office replies for a mailbox.

Use -AutoReplyState Enabled to start now with no end date. -ExternalAudience accepts None, Known or All.

Turn off automatic replies.

Show a mailbox's automatic reply state and messages.