Skip to main content

Calculating Mailbox Sizes using Exchange Web Services and Powershell

Normally if you want to work out the size of a mailbox or the size of a mailbox folder as an administrator you would use get-mailboxstatistics and get-mailboxfolderstatistics the Exchange Management Shelll cmdlets which are the fastest and easiest way of retrieving this information on 2007 and 2010. However if you want to get the Mailbox size using normal user rights or the EMS cmdlets aren't an option then EWS can be used. There is no one property inside a mailbox that can be used to get the total size of a mailbox so like you needed to do in 2003 and earlier to calculate the size of a mailbox you need to get the size of each mailbox folder then sum these together. To get the Size of the Mailbox Folder and Deleted Items within a folder requires the use of the following extended Mapi properties

PR_MESSAGE_SIZE_EXTENDED and PR_DELETED_MESSAGE_SIZE_EXTENDED

To get the properties on all of the folders in a Mailbox a Deep Traversal findfolders operations from the Root of the Mailbox can be used.

One of useful things you can do with EWS that you can't do in EMS with the cmdlets is filter this query by the Mapi FolderClass (which is different from the folderscope property). In the large script posted below I've commented out the filter to do this but the lines are

##$folderItemType = "IPF.Note"
##$sfSearchFilter = new-object Microsoft.Exchange.WebServices.Data.SearchFilter+IsEqualTo([Microsoft.Exchange.WebServices.Data.FolderSchema]::FolderClass, $folderItemType)
##$fiResult = $Service.FindFolders($folderidcnt,$sfSearchFilter,$fvFolderView)


The normal EWS Managed API power shell script I've put a download of here the code looks like

$MailboxName = "user@domain.com"
##$folderItemType = "IPF.Note"
$rptCollection = @()


$dllpath = "C:\Program Files\Microsoft\Exchange\Web Services\1.1\Microsoft.Exchange.WebServices.dll"
[void][Reflection.Assembly]::LoadFile($dllpath)
$service = New-Object Microsoft.Exchange.WebServices.Data.ExchangeService([Microsoft.Exchange.WebServices.Data.ExchangeVersion]::Exchange2007_SP1)


$windowsIdentity = [System.Security.Principal.WindowsIdentity]::GetCurrent()
$sidbind = "LDAP://<SID=" + $windowsIdentity.user.Value.ToString() + ">"
$aceuser = [ADSI]$sidbind
$service.AutodiscoverUrl($aceuser.mail.ToString(),{$true})

$TotalItemCount = 0
$TotalItemSize = 0

"Checking : " + $MailboxName
$folderidcnt = new-object Microsoft.Exchange.WebServices.Data.FolderId([Microsoft.Exchange.WebServices.Data.WellKnownFolderName]::Root,$MailboxName)
$fvFolderView = New-Object Microsoft.Exchange.WebServices.Data.FolderView(10000)
$fvFolderView.Traversal = [Microsoft.Exchange.WebServices.Data.FolderTraversal]::Deep;
$psPropertySet = new-object Microsoft.Exchange.WebServices.Data.PropertySet([Microsoft.Exchange.WebServices.Data.BasePropertySet]::FirstClassProperties)
$PR_MESSAGE_SIZE_EXTENDED = new-object Microsoft.Exchange.WebServices.Data.ExtendedPropertyDefinition(3592,[Microsoft.Exchange.WebServices.Data.MapiPropertyType]::Long);
$PR_DELETED_MESSAGE_SIZE_EXTENDED = new-object Microsoft.Exchange.WebServices.Data.ExtendedPropertyDefinition(26267,[Microsoft.Exchange.WebServices.Data.MapiPropertyType]::Long);
$PR_DELETED_MSG_COUNT = new-object Microsoft.Exchange.WebServices.Data.ExtendedPropertyDefinition(26176,[Microsoft.Exchange.WebServices.Data.MapiPropertyType]::Integer);
$psPropertySet.Add($PR_MESSAGE_SIZE_EXTENDED);
$psPropertySet.Add($PR_DELETED_MESSAGE_SIZE_EXTENDED);
$psPropertySet.Add($PR_DELETED_MSG_COUNT);
$fvFolderView.PropertySet = $psPropertySet;
##$sfSearchFilter = new-object Microsoft.Exchange.WebServices.Data.SearchFilter+IsEqualTo([Microsoft.Exchange.WebServices.Data.FolderSchema]::FolderClass, $folderItemType)
##$fiResult = $Service.FindFolders($folderidcnt,$sfSearchFilter,$fvFolderView)
$fiResult = $Service.FindFolders($folderidcnt,$fvFolderView)
foreach($ffFolder in $fiResult.Folders){
$TotalItemCount = $TotalItemCount + $ffFolder.TotalCount;
$FolderSize = $null;
if ($ffFolder.TryGetProperty($PR_MESSAGE_SIZE_EXTENDED,[ref] $FolderSize))
{
$TotalItemSize = $TotalItemSize + [Int64]$FolderSize
}
$DeletedItemFolderSize = $null;
if ($ffFolder.TryGetProperty($PR_DELETED_MESSAGE_SIZE_EXTENDED, [ref] $DeletedItemFolderSize))
{
$TotalDeletedItemSize = $TotalDeletedItemSize + [Int64]$DeletedItemFolderSize
}
$DeletedMsgCount = $null;
if ($ffFolder.TryGetProperty($PR_DELETED_MSG_COUNT, [ref] $DeletedMsgCount))
{
$TotalDeletedItemCount = $TotalDeletedItemCount + [Int32]$DeletedMsgCount;
}
}
$rptobj = "" | select DisplayName,LegacyDN,TotalItemSize,TotalItemCount,TotalDeletedItemSize,TotalDeletedItemCount
$rptobj.DisplayName = $_.DisplayName
$rptobj.LegacyDN = $_.LegacyExchangeDN
$rptobj.TotalItemCount = $TotalItemCount
$rptobj.TotalItemSize = $TotalItemSize
$rptobj.TotalDeletedItemSize = $TotalDeletedItemSize
$rptobj.TotalDeletedItemCount = $TotalDeletedItemCount
$rptCollection += $rptobj

$rptCollection

Popular posts from this blog

Testing and Sending email via SMTP using Opportunistic TLS and oAuth in Office365 with PowerShell

As well as EWS and Remote PowerShell (RPS) other mail protocols POP3, IMAP and SMTP have had OAuth authentication enabled in Exchange Online (Official announcement here ). A while ago I created  this script that used Opportunistic TLS to perform a Telnet style test against a SMTP server using SMTP AUTH. Now that oAuth authentication has been enabled in office365 I've updated this script to be able to use oAuth instead of SMTP Auth to test against Office365. I've also included a function to actually send a Message. Token Acquisition  To Send a Mail using oAuth you first need to get an Access token from Azure AD there are plenty of ways of doing this in PowerShell. You could use a library like MSAL or ADAL (just google your favoured method) or use a library less approach which I've included with this script . Whatever way you do this you need to make sure that your application registration  https://docs.microsoft.com/en-us/azure/active-directory/develop/quickstart-register-

How to test SMTP using Opportunistic TLS with Powershell and grab the public certificate a SMTP server is using

Most email services these day employ Opportunistic TLS when trying to send Messages which means that wherever possible the Messages will be encrypted rather then the plain text legacy of SMTP.  This method was defined in RFC 3207 "SMTP Service Extension for Secure SMTP over Transport Layer Security" and  there's a quite a good explanation of Opportunistic TLS on Wikipedia  https://en.wikipedia.org/wiki/Opportunistic_TLS .  This is used for both Server to Server (eg MTA to MTA) and Client to server (Eg a Message client like Outlook which acts as a MSA) the later being generally Authenticated. Basically it allows you to have a normal plain text SMTP conversation that is then upgraded to TLS using the STARTTLS verb. Not all servers will support this verb so if its not supported then a message is just sent as Plain text. TLS relies on PKI certificates and the administrative issue s that come around certificate management like expired certificates which is why I wrote th

The MailboxConcurrency limit and using Batching in the Microsoft Graph API

If your getting an error such as Application is over its MailboxConcurrency limit while using the Microsoft Graph API this post may help you understand why. Background   The Mailbox  concurrency limit when your using the Graph API is 4 as per https://docs.microsoft.com/en-us/graph/throttling#outlook-service-limits . This is evaluated for each app ID and mailbox combination so this means you can have different apps running under the same credentials and the poor behavior of one won't cause the other to be throttled. If you compared that to EWS you could have up to 27 concurrent connections but they are shared across all apps on a first come first served basis. Batching Batching in the Graph API is a way of combining multiple requests into a single HTTP request. Batching in the Exchange Mail API's EWS and MAPI has been around for a long time and its common, for email Apps to process large numbers of smaller items for a variety of reasons.  Batching in the Graph is limited to a m
All sample scripts and source code is provided by for illustrative purposes only. All examples are untested in different environments and therefore, I cannot guarantee or imply reliability, serviceability, or function of these programs.

All code contained herein is provided to you "AS IS" without any warranties of any kind. The implied warranties of non-infringement, merchantability and fitness for a particular purpose are expressly disclaimed.