Skip to main content

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 https://msdn.microsoft.com/en-us/library/office/dn818490(v=exchg.150).aspx and https://msdn.microsoft.com/en-us/library/office/dn818491(v=exchg.150).aspx. 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);
        $RequestStream.Close();
        $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 https://github.com/gscales/Powershell-Scripts/blob/master/EnumerateItemsInPublicFolder.ps1

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

https://github.com/gscales/Powershell-Scripts/blob/master/PublicFolderItemAge.ps1




Popular posts from this blog

Using the MSAL (Microsoft Authentication Library) in EWS with Office365

Last July Microsoft announced here they would be disabling basic authentication in EWS on October 13 2020 which is now a little over a year away. Given the amount of time that has passed since the announcement any line of business applications or third party applications that you use that had been using Basic authentication should have been modified or upgraded to support using oAuth. If this isn't the case the time to take action is now. When you need to migrate a .NET app or script you have using EWS and basic Authentication you have two Authentication libraries you can choose from ADAL - Azure AD Authentication Library (uses the v1 Azure AD Endpoint) MSAL - Microsoft Authentication Library (uses the v2 Microsoft Identity Platform Endpoint) the most common library you will come across in use is the ADAL libraries because its been around the longest, has good support across a number of languages and allows complex authentications scenarios with support for SAML etc. The

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

A walk-though using the Graph API Mailbox reports in Powershell

Quite recently the Reporting side of the Graph API has moved in GA from beta, there are quite a number of reports that can be run across various Office365 surfaces but in this post I'm going to focus on the Mailbox related ones. Accessing Office365 Reports using Powershell is nothing new and has been available in the previous reporting endpoint  https://msdn.microsoft.com/en-us/library/office/jj984326.aspx however from the end of January many of these cmdlets are now being depreciated in favour of the Graph API  https://msdn.microsoft.com/en-us/library/office/dn387059.aspx . Prerequisites  In comparison to using the Remote PowerShell cmdlets where only the correct Office365 Admin permissions where needed, to use the new Graph API reports endpoint you need to use OAuth for authentication so this requires an Application Registration  https://developer.microsoft.com/en-us/graph/docs/concepts/auth_overview  that is then given the correct oAuth Grants to use the Reports EndPoin
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.