#################################
# Count emails in PST file      #
# MK 11/2016                    #
# Rev1.0                        #
#################################

#Check if Outlook is installed
Get-ItemProperty HKLM:\SOFTWARE\Classes\Outlook.Application | Select-Object PSPath -OutVariable outlook
if (!$outlook -match "Outlook.Application"){ 
Write-Host "Outlook is not installed on this machine, Press any key to continue ..."
$null = $Host.UI.RawUI.ReadKey('NoEcho,IncludeKeyDown');
}

#Path to PST File
$strPSTPath = "PATHTOPST"

#Create Outlook COM Object
$objOutlook = New-Object -com Outlook.Application
$objNameSpace = $objOutlook.GetNamespace("MAPI")

#Try to load the PST into Outlook
try {
$objNameSpace.AddStore($strPSTPath)
}
catch
{
Write-Host "Could not load pst - usually this is because the file is locked by another process or is too big (try opening in outlook to see the full error) Press any key to continue ..."
$null = $Host.UI.RawUI.ReadKey('NoEcho,IncludeKeyDown');
}

#Try to load the Outlook Folders
try {
$PST = $objnamespace.stores | ? { $_.FilePath -eq $strPSTPath }
}
catch
{
Write-Host "You have another PST added to outlook that cannot be accessed or found, please remove then re-run this script. Press any key to continue ..."
$null = $Host.UI.RawUI.ReadKey('NoEcho,IncludeKeyDown');
}

#Browse to PST Root
$root = $PST.GetRootFolder()

#Get top level folders
$subfolders = $root.Folders

#count items in PST Root
$rootcount = $root.items.count

#Write root count (usually zero)
Write-Host "PST Root Folder Contains" $rootcount "Items"

#Start Counter
$counter = $rootcount

#Iterate all folders (sub folders, ONLY 6 layers deep)
# root ("/")- L1 -L2 -L3-L4-L5-L6
# L1
foreach ($L1folder in $subfolders)
{
  $count = $L1folder.items.count
  Write-Host "Folder" $L1folder.FolderPath "Contains" $count "Items"
  $counter += $count
  # L2
  foreach ($L2folder in $L1folder.Folders)
  {
    $count = $L2folder.items.count
    Write-Host "Folder" $L2folder.FolderPath "Contains" $count "Items"
    $counter += $count
	# L3
    foreach ($L3folder in $L2folder.Folders)
    {
      $count = $L3folder.items.count
      Write-Host "Folder" $L3folder.FolderPath "Contains" $count "Items"
      $counter += $count
      # L4
      foreach ($L4folder in $L3folder.Folders)
      {
        $count = $L4folder.items.count
        Write-Host "Folder" $L4folder.FolderPath "Contains" $count "Items"
        $counter += $count
        # L5
        foreach ($L5folder in $L4folder.Folders)
        {
          $count = $L5folder.items.count
          Write-Host "Folder" $L5folder.FolderPath "Contains" $count "Items"
          $counter += $count
          # L6
          foreach ($L6folder in $L5folder.Folders)
          {
            $count = $L6folder.items.count
            Write-Host "Folder" $L6folder.FolderPath "Contains" $count "Items"
            $counter += $count
            # L7
            foreach ($L7folder in $L6folder.Folders)
            {
              $count = $L7folder.items.count
              Write-Host "Folder" $L7folder.FolderPath "Contains" $count "Items"
              $counter += $count
              # L8
              foreach ($L8folder in $L7folder.Folders)
              {
                $count = $L8folder.items.count
                Write-Host "Folder" $L8folder.FolderPath "Contains" $count "Items"
                $counter += $count
              }	
            }		
          }			
        }
      }
    }
  }
}

#Write total count
Write-Host "Total Items" $counter -ForegroundColor Red