Thursday, April 28, 2016

EWS Bascis : Accessing Public Folders and Public Folder Content

As well as Mailboxes and Archives, Public Folders are another place you may want to use EWS to enumerate Items to do some enhanced reporting. Building on the Enumerate script from the last two post, this post will cover how to modify this script to enable access Public Folder and Public Folder Items.

EWS Changes

To change the Mailbox code we have to access public folders requires one big change in the Mailbox script we have the line

$folderid = new-object Microsoft.Exchange.WebServices.Data.FolderId([Microsoft.Exchange.WebServices.Data.WellKnownFolderName]::MsgFolderRoot,$SmtpAddress) 

in the FolderIdFromPath function. To access a Public folder we need to change this to

$folderid = new-object Microsoft.Exchange.WebServices.Data.FolderId([Microsoft.Exchange.WebServices.Data.WellKnownFolderName]::PublicFoldersRoot) 

And that's pretty much it apart from renaming the function to PublicFolderIdFromPath this is all you have to do. One thing you can't do with Public Folders vs what you can do with Mailboxs and Archive folders is do a DeepTraversal of all the folders in a folder hierarchy. For the basic enumeration script this isn't a big deal because all the searches are done at a shallow level.

Exchange 2013 up

For Exchange 2013,2016 and Exchange Online there is one other change you should make to this script which is to add the X-AnchorHeader and X-PublicFolderMailbox headers to ensure routing happens correctly as per and It gets a little complicated here but because the Hierarchy and content maybe located in a different Public Folder Mailboxes you have to use 2 different discovery mechanisms both the EWS Managed API discover like

        $ExchangeVersion = [Microsoft.Exchange.WebServices.Data.ExchangeVersion]::Exchange2013_SP1
        $AutoDiscoverService =  New-Object  Microsoft.Exchange.WebServices.Autodiscover.AutodiscoverService($ExchangeVersion);
        $creds = New-Object System.Net.NetworkCredential($Credentials.UserName.ToString(),$Credentials.GetNetworkCredential().password.ToString()) 
        $AutoDiscoverService.Credentials = $creds
        $AutoDiscoverService.EnableScpLookup = $false;
        $AutoDiscoverService.RedirectionUrlValidationCallback = {$true};
        $AutoDiscoverService.PreAuthenticate = $true;
        $AutoDiscoverService.KeepAlive = $false;      
        $gsp = $AutoDiscoverService.GetUserSettings($MailboxName,[Microsoft.Exchange.WebServices.Autodiscover.UserSettingName]::AutoDiscoverSMTPAddress);

and a POX Autodiscover (plain old XML) method like

        $AutoDiscoverRequest = [System.Net.HttpWebRequest]::Create($AutoDiscoverService.url.ToString().replace(".svc",".xml"));
        $bytes = [System.Text.Encoding]::UTF8.GetBytes($auDisXML);
        $AutoDiscoverRequest.ContentLength = $bytes.Length;
        $AutoDiscoverRequest.ContentType = "text/xml";
        $AutoDiscoverRequest.UserAgent = "Microsoft Office/16.0 (Windows NT 6.3; Microsoft Outlook 16.0.6001; Pro)";            
        $AutoDiscoverRequest.Headers.Add("Translate", "F");
        $AutoDiscoverRequest.Method = "POST";
        $AutoDiscoverRequest.Credentials = $creds;
        $RequestStream = $AutoDiscoverRequest.GetRequestStream();
        $RequestStream.Write($bytes, 0, $bytes.Length);
        $AutoDiscoverRequest.AllowAutoRedirect = $truee;
        $Response = $AutoDiscoverRequest.GetResponse().GetResponseStream()
        $sr = New-Object System.IO.StreamReader($Response)
        [XML]$xmlReposne = $sr.ReadToEnd()
        if($xmlReposne.Autodiscover.Response.User.AutoDiscoverSMTPAddress -ne $null)
            write-host ("Public Folder Content Routing Information Header : " + $xmlReposne.Autodiscover.Response.User.AutoDiscoverSMTPAddress)  
            $service.HttpHeaders["X-AnchorMailbox"] = $xmlReposne.Autodiscover.Response.User.AutoDiscoverSMTPAddress    
            $service.HttpHeaders["X-PublicFolderMailbox"] = $xmlReposne.Autodiscover.Response.User.AutoDiscoverSMTPAddress              

I've put a full copy of this enumerate script up on git hub

For one example of what you can do with it if we take the sample from the last post on ItemAge we can create an ItemAge script for public folder items. eg

Tuesday, April 12, 2016

EWS Basics : Reporting on the Age of Items in a Folder

One of the more common questions I get is around some of the EWS Item Age scripts I've written in the past. If we take the script I introduced in the first Basics post with some easy modifications we can turn this script that already enumerates all the Items in a folder into a script that will report on age of the Items in a folder. So in this post I'm going to try to explain a little better the changes that you would need to make.

EWS Changes

The EWS changes that need to be made to the basics script are to the Propertyset that is used in the FindItems Operation. A PropertySet in EWS basically tells Exchange which properties you want to be returned. So to make this script as efficient as possible we want to restrict Exchange to just returning the Size and DateTime the messages where received or created. So these are the only changes that are needed for the EWS side

$ivItemView =  New-Object Microsoft.Exchange.WebServices.Data.ItemView(1000) 
$ItemPropset= new-object Microsoft.Exchange.WebServices.Data.PropertySet([Microsoft.Exchange.WebServices.Data.BasePropertySet]::IdOnly)
$ivItemView.PropertySet = $ItemPropset


When your reporting on the age of Items your basically aggregating the part of the Date/Time a Message was received. To do the aggregation in this script I'm just using a Hashtable which there is a good description of at . The way I'm using them to aggregate the number of Messages and the size of the messages for the Year a Message was received in. To get the Year a message was received in the item enumeration section of the script I'm using this simple function

$dateVal = $null
if($Item.TryGetProperty([Microsoft.Exchange.WebServices.Data.ItemSchema]::DateTimeReceived,[ref]$dateVal )-eq $false){
 $dateVal = $Item.DateTimeCreated
What this does is loads the DateTimeReceived property into the $dataVal variable and if that property isn't available (eg the message maybe a draft) it uses the DateTime created property.

Once we have this value its just a matter of firstly using the Year property of the (DateTime) Class and then we aggregate this value with the Hashtable. In the Values collection of the HashTable I'm using a Custom object (see that does the aggregation part.  eg

 $rptCollection[$dateVal.Year].TotalNumber += 1
 $rptCollection[$dateVal.Year].TotalSize += [Int64]$Item.Size
 $rptObj = "" | Select Year,TotalNumber,TotalSize
 $rptObj.TotalNumber = 1
        $rptObj.Year = $dateVal.Year
 $rptObj.TotalSize = [Int64]$Item.Size

At the end of this we can just write the HashTable Values collection back to output Pipeline using write-object taking advantage of the sort-object cmdlet to make sure the values are sorted descending by Year

Write-Output $rptCollection.Values | Sort-Object -Property Year -Descending

I've put a copy of this script on GitHub here

An example of running this script would look like