Skip to main content

How to log EWS Traces to a file in PowerShell

If your using the EWS Managed API in your PowerShell scripts and you need to do some extended debugging to work out why a script isn't working the way you expect in certain environments you can do this by using Tracing as described in https://docs.microsoft.com/en-us/previous-versions/office/developer/exchange-server-2010/dd633676(v=exchg.80) . What this does once it is enabled is it outputs all the requests and responses that are sent to and from the Exchange server so you can see exactly what is taking place and potentially more information on particular errors that are occurring.  So in a EWS Managed API script to enable this you just need to set the TraceEnabled property on the ExchangeService object to true eg

$server.TraceEnabled = $true

And you will then start seeing traces like the following in the console



A much cleaner way of capturing these traces is to configure the EWS Managed API to use a separate log file to log them to a file so you can review them later. To do this it requires that you create a class that implements an Interface of ITraceListener https://github.com/OfficeDev/ews-managed-api/blob/70bde052e5f84b6fee3a678d2db5335dc2d72fc3/Interfaces/ITraceListener.cs .  In C# this a pretty trivial thing to do but in PowerShell its a little more complicated. However using Add-Type in PowerShell gives you the ability to simply define your own custom class that implements the interface and then compile this on the go which then makes it available in your PS Session. The basic steps are

  • You need to define an class that implements the interface (through inheritance) and the methods defined in that interface in this case it only has one called Trace
  • Define your own code to perform the underlying logging in my example its a simple one liner that will append the Tracemessage to a File the path of which is held in the Public Property I've defined in my class 
  • Use Add-Type to compile the class and make it available in your PS Session
  • Create a Instance of the Class you just defined eg here's a function to do it
eg
function TraceHandler(){
$sourceCode = @"
    public class ewsTraceListener : Microsoft.Exchange.WebServices.Data.ITraceListener
    {
        public System.String LogFile {get;set;}
        public void Trace(System.String traceType, System.String traceMessage)
        {
            System.IO.File.AppendAllText(this.LogFile, traceMessage);
        }
    }
"@    

    Add-Type -TypeDefinition $sourceCode -Language CSharp -ReferencedAssemblies $Script:EWSDLL
    $TraceListener = New-Object ewsTraceListener
   return $TraceListener


}

Then in your PS Code just use the Instance (Object) of the Class you just created (first setting the LogFile property to path of the File you want to log to) eg

        $service.TraceEnabled = $true
        $TraceHandlerObj = TraceHandler
        $TraceHandlerObj .LogFile = "c:\Tracing\$MailboxName.log"
        $service.TraceListener = $TraceHandlerObj 

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.