Microsoft 365 PowerShell

One-time setup

1. Install PowerShell 7. Windows PowerShell 5.1 also works, but 7 is faster and better supported:

   winget install --id Microsoft.PowerShell

2. Open PowerShell 7 and install the two modules for your user account. No admin rights are needed:

   Install-Module ExchangeOnlineManagement -Scope CurrentUser
   Install-Module Microsoft.Graph -Scope CurrentUser

   Answer Y or A if asked to trust the PSGallery repository.
3. To update them later:

   Update-Module ExchangeOnlineManagement, Microsoft.Graph

Connect to Exchange Online

Connect-ExchangeOnline -UserPrincipalName [email protected]

A Microsoft sign-in window opens, and MFA is supported. When you're finished:

Disconnect-ExchangeOnline -Confirm:$false

Export the members of a distribution list

$DGName = "All Staff"
Get-DistributionGroupMember -Identity $DGName -ResultSize Unlimited |
    Select-Object Name, PrimarySmtpAddress |
    Export-Csv "$env:USERPROFILE\Documents\$DGName.csv" -NoTypeInformation -Encoding UTF8

Change "All Staff" to the list's name. The CSV is saved in your Documents folder under the list's name and opens in Excel.

To export every distribution list to one file:

Get-DistributionGroup -ResultSize Unlimited | ForEach-Object {
    $group = $_
    Get-DistributionGroupMember -Identity $group.Identity -ResultSize Unlimited |
        Select-Object @{n='Group';e={$group.DisplayName}}, Name, PrimarySmtpAddress
} | Export-Csv "$env:USERPROFILE\Documents\All-Distribution-Lists.csv" -NoTypeInformation -Encoding UTF8

Shared mailbox access

Give someone full access (the mailbox appears in their Outlook automatically):

Add-MailboxPermission -Identity [email protected] -User [email protected] -AccessRights FullAccess -InheritanceType All -AutoMapping $true

Let them send as the mailbox:

Add-RecipientPermission -Identity [email protected] -Trustee [email protected] -AccessRights SendAs -Confirm:$false

Convert a departed user's mailbox to a shared mailbox, so it no longer needs a licence:

Set-Mailbox -Identity [email protected] -Type Shared

Forward a mailbox

Set-Mailbox -Identity [email protected] -ForwardingSmtpAddress [email protected] -DeliverToMailboxAndForward $true

Use -DeliverToMailboxAndForward $false if you don't want a copy kept in the original mailbox. To remove forwarding, set -ForwardingSmtpAddress $null.

Trace a message

Find out whether an email was delivered, blocked or quarantined (covers the last 10 days):

Get-MessageTraceV2 -SenderAddress [email protected] -StartDate (Get-Date).AddDays(-2) -EndDate (Get-Date) |
    Select-Object Received, SenderAddress, RecipientAddress, Subject, Status

Get-MessageTraceV2 replaces the older Get-MessageTrace, which is being retired. Update the module if the command isn't found.

Permanently delete a user account

A deleted user stays in the recycle bin for 30 days. During that time you can't create a new account with the same username. To free it up immediately:

From the admin center

1. Go to entra.microsoft.com → Users → Deleted users.
2. Select the user and click Delete permanently.

From PowerShell

Connect-MgGraph -Scopes "User.DeleteRestore.All"

# Find the deleted user and copy its Id
Get-MgDirectoryDeletedItemAsUser -All |
    Select-Object Id, DisplayName, UserPrincipalName, DeletedDateTime

# Permanently delete it
Remove-MgDirectoryDeletedItem -DirectoryObjectId "<Id from above>"