Get-ExchangeDistributionGroupMemberInfo

Exchange: Retrieves members of a Distribution Group

Script

#Requires -Version 5.1

[CmdletBinding()]
Param (
    [Parameter(Mandatory = $true)]
    [string]$Identity,

    [switch]$Recursive,

    [ValidateSet('All', 'Mailbox', 'Group', 'Contact')]
    [string]$MemberType = 'All'
)

Process {
    try {
        $group = Get-DistributionGroup -Identity $Identity -ErrorAction Stop
        
        function Get-ExchangeMembers {
            param($GroupId)
            $rawMembers = Get-DistributionGroupMember -Identity $GroupId -ErrorAction SilentlyContinue
            foreach ($member in $rawMembers) {
                $isGroup = $member.RecipientType -match 'Group'
                
                $match = $false
                if ($MemberType -eq 'All') { $match = $true }
                elseif ($MemberType -eq 'Mailbox' -and $member.RecipientType -match 'Mailbox') { $match = $true }
                elseif ($MemberType -eq 'Group' -and $isGroup) { $match = $true }
                elseif ($MemberType -eq 'Contact' -and $member.RecipientType -match 'Contact') { $match = $true }

                if ($match) {
                    [PSCustomObject]@{
                        DisplayName    = $member.DisplayName
                        PrimarySmtpAddress = $member.PrimarySmtpAddress
                        RecipientType  = $member.RecipientType
                        ParentGroup    = $GroupId
                    }
                }

                if ($Recursive -and $isGroup) {
                    Get-ExchangeMembers -GroupId $member.DistinguishedName
                }
            }
        }

        $results = Get-ExchangeMembers -GroupId $group.DistinguishedName
        Write-Output ($results | Sort-Object DisplayName -Unique)
    }
    catch {
        throw
    }
}

Customize

Identity string

Specifies the Identity of the distribution group.

Recursive switch

Off

If set, recursively expands nested groups to show all effective members.

MemberType string

Optional filter for the type of members to return (e.g., Mailbox, Group, Contact).