Export a distribution group's information from Exchange Online

Export-DistributionGroupInfo.ps1

function Export-DistributionGroupInfo {
  <#
  .SYNOPSIS
    This function exports the information for an Exchange Online distribution group.

  .DESCRIPTION
    This function takes in an array of distribution group PrimarySmtpAddresses. Each group is looked up and their information
    is condensed to a single .csv file which is exported to your Downloads directory.

  .PARAMETER Groups
    The PrimarySmtpAddress(es) of the distribution group(s) for which you'd like to export information.

    Required            : true
    ValueFromPipeline   : true
    Type                : array

  .PARAMETER RevealInFileSystem
    Reveal the output file in File Explorer (requires Windows platform).

    Required            : false
    ValueFromPipeline   : false
    Type                : switch

  .PARAMETER OpenOutputFile
    Open the output file in the default application for .csv files.

    Required            : false
    ValueFromPipeline   : false 
    Type                : switch

  .INPUTS
    PrimarySmtpAddress(es)

  .OUTPUTS
    DgInfoExport_<PrimarySmtpAddress>.csv

  .NOTES
    Author              : Griff Barker ([email protected])
    Change Date         : 2025-06-04
    Purpose/Change      : Initial development

  .EXAMPLE
    # Dot-source the function then run it to export a single group's information
    . "C:\Path\To\Export-DistributionGroupInfo.ps1"
    Export-DistributionGroupInfo.ps1 -Groups @(
      '[email protected]'
    )

  .EXAMPLE
    # Dot-source the function then run it to export multiple groups' information
    . "C:\Path\To\Export-DistributionGroupInfo.ps1"
    Export-DistributionGroupInfo.ps1 -Groups @(
      '[email protected]',
      '[email protected]',
      '[email protected]'
    )

  .LINK
    https://gist.github.com/griffeth-barker/fe95114d2037f4ff874a3f137854cd34
  #>

  [CmdletBinding()]
  param (
      [Parameter(Mandatory = $true, ValueFromPipeline = $true)]
      [array]
      $Groups,
      [Parameter(Mandatory = $false, ParameterSetName = 'PostExportAction')]
      [switch]
      $RevealInFileSystem,
      [Parameter(Mandatory = $false, ParameterSetName = 'PostExportAction')]
      [switch]
      $OpenOutputFile
  )

  begin {
    #Requires -Modules ExchangeOnlineManagement
    
    Write-Debug "Importing module: 'ExchangeOnlineManagement'"
    Import-Module -Name ExchangeOnlineManagement

    Write-Debug "Creating system collection: 'reportData'"
    $reportData = [System.Collections.Generic.List[psobject]]::new()

    if (-not (Get-ConnectionInformation)) {
      Write-Debug "Connecting to Exchange Online"
      try {
        Write-Debug "If the function appears to be hung here, there may be a pop-up window in the background waiting for you to log in to Exchange Online."
        Connect-ExchangeOnline -ShowBanner:$false -ErrorAction Stop
        Write-Debug $(Get-ConnectionInformation)
      }
      catch {
        Write-Error "Failed to connect to Exchange Online"
        Write-Error $_.Exception.Message
        exit 1
      }
    }
  }

  process {
    foreach ($group in $Groups) {
      Write-Verbose "Obtaining information for distribution group: '$group'"
      Write-Verbose "Obtaining information for distribution group: '$group'"
      try {
        $reportData.Add($(Get-DistributionGroup -Identity "$group" -ErrorAction Stop | Select-Object -Property *) )
      }
      catch {
        Write-Warning "Failed to obtain information for $group"
        Write-Warning $_.Exception.Message
      }
    }
  }

  end {
    Write-Verbose "Exporting information to file"
    $exportSplat = @{
      InputObject = $($reportData)
      Path = "$($env:USERPROFILE)\Downloads\DgInfoExport_$($group.replace('@','_').replace('.','_')).csv"
      NoTypeInformation = $true
      Force = $true
    }

    Write-Debug "Exporting data to '$($exportSplat.Path)'"
    try {
      Export-Csv @exportSplat
    }
    catch {
      Write-Warning "Failed to export output file"
      Write-Debug "Failed to write file to '$($exportSplat.Path)'"
      Write-Debug $_.Exception.Message
    }

    Write-Debug "Disconnecting from Exchange Online"
    Disconnect-ExchangeOnline -Confirm:$false

    if ($RevealInFileSystem) {
      if ($IsWindows -eq $true) {
        Write-Verbose "Revealing output file in the file system"
        Start-Process -Path "explorer.exe" -ArgumentList "$($env:USERPROFILE)\Downloads"
      }
      else {
        Write-Warning "Opening output file is currently only supported on Windows platforms."
        Write-Debug "Opening output path requires 'explorer.exe'"
      }
    }
    if ($OpenOutputFile) {
      Write-Verbose "Opening output file in default application for .csv files"
      Write-Debug "Opening '$($explortSplat.Path)'"
      Invoke-Item -Path "$($exportSplat.Path)"
    }
  }
}

# Optionally, uncommend the below lines and update the `-Groups` parameter to run the function immediately without needing to dot-source the function file.
# Export-DistributionGroupInfo -Groups @(
#   '[email protected]',
#   '[email protected]',
#   '[email protected]'
# )