Glen's Exchange and Office 365 Dev Blog

One of the new features added to the Microsoft Graph recently was the ability to create and send Mime Messages (you have been able to get Message as Mime for a while). This is useful in a number of different scenarios especially when trying to create a Message with inline Images which has historically been hard to do with both the Graph and EWS (if you don't use MIME). It also opens up using SMIME for encryption and a more easy migration path for sending using SMTP in some apps. MimeKit is a great open source library for parsing and creating MIME messages so it offers a really easy solution for tackling this issue. The current documentation on Send message via MIME lacks any real sample so I've put together a quick console app that use MSAL, MIME kit and the Graph SDK to send a Message via MIME. As the current Graph SDK also doesn't support sending via MIME either there is a workaround for this in the future my guess is this will be supported.

 One of the more complex things to migrate in EWS when migrating to the Graph API is any directory access code that uses one of the following EWS operations FindPeople ResolveName ExpandGroup (ExpandDL) or if your using OnPrem you maybe using System.DirectoryServices to do direct LDAP requests of Active Directory. With the Microsoft Graph API these Directory based mail operations don't exist, because you have full access to the underlying AzureAD, so in theory everything should be achievable without these type of operations. For the most part this is correct where is starts to get a little grayer is around this like Address Lists and Exchange recipient types mostly because the Graph doesn't expose the following underlying Active Directory properties msExchRecipientDisplayType msExchRecipientTypeDetails msExchRemoteRecipientType so this can be a limitation if your migrating from LDAP code and some FindPeople implementations if your searching based on AddressList. Microsoft Grap...

There's been a few contact creation scripts popup recently for the Graph API like this as well as a few questions on the forums around this topic lately. None of these examples and questions are taking advantage of using batching in the Microsoft Graph which will give you a significant uplift in performance vs the single request method when creating larger numbers of items and also help you a little around throttling. I've added a new post to my Graph 101 binder  on GitHub that includes an example of doing a CSV Contact import using batching and Service Principal Authentication  https://github.com/gscales/Graph-Powershell-101-Binder/blob/master/Contacts/Batch%20Importing%20Contacts.md   If your interested in a EWS version that can use larger batches (eg 60-100 contacts per request) I've also include an example on GitHub for this  https://github.com/gscales/Powershell-Scripts/blob/master/Graph101/BatchContactCreationEWS.ps1

Out of Office (or automaticRepliesSetting) can be used for a vast number of different applications. For example in this Teams In/Out board   With the Microsoft Graph API there are two ways that can be used to get the automaticRepliesSetting either via the Mailbox setting Endpoint eg https://docs.microsoft.com/en-us/graph/api/resources/automaticrepliessetting?view=graph-rest-1.0 Or you can use MailTips which was the method i used in the Teams Apps eg https://docs.microsoft.com/en-us/graph/api/user-getmailtips?view=graph-rest-1.0&tabs=http eg When it comes to setting the OOF you must use the Mailboxsettings endpoint What is better ? for getting the OOF settings on a large number of users getmailtips because you can request up to 100 users in one request while if your batching Mailboxsetting you can only have a max of 20 user in a single batch. Permission and Authentication  One consideration for the Mailboxsettings endpoint is there is no ability to use Delegate permiss...

The "Tag for external email messages received" feature was introduced into Office365 recently to help people better to identify mail that comes from external sender vs internal sender see this for more info on this feature . What happens when you enable this feature is that for messages with External sender a new Mapi property is set on those messages eg For messages from internal senders the property doesn't appear to get set and if the feature isn't enabled in your tenant then you won't see this property either. You can negate the boolean value of the property which will turn off the external tag. Using it in the Microsoft Graph API If you want to use it in the Microsoft Graph API when you retrieve messages you can include this as a SingleValueExtendedProperties eg for Retrieving and filtering message you can use I've included this in my Get LastEmail 101 graph sample  if you want to try this in a real mailbox eg you can do  Get-LastEmail -InternalSender -M...

As the information on how to do this would cover multiple posts, I've bound this into a series of mini post docs in my GitHub Repo to try and make this subject a little easier to understand and hopefully navigate for most people.   The Binder index is  https://gscales.github.io/Graph-Powershell-101-Binder/   The topics covered are How you can access the Recoverable Items Folders (and get the size of these folders)  How you can access and search for items in the Deletions and Purges Folders and also how you can Export an item to an Eml from that folder How you can Restore a Deleted Item back to the folder it was deleted from (using the Last Active Parent FolderId) and the sample script is located  https://github.com/gscales/Powershell-Scripts/blob/master/Graph101/Dumpster.ps1

Searching on the Categories property of an Email can pose a challenge because this property is a Multi-valued String property (which aren't that common in email) eg in a Message the property may look like the following So this needs to be queried in a different way then a normal String or single valued property in an Email would, where you could use a number of filter options (eg equal, contains,startswith). In EWS it was only possible to query this property using AQS because of the way SearchFilters translated to the underlying ROP based restrictions used by the Exchange Mailbox Store. In the Microsoft Graph the Linq format in Filters does translate more favourably so can be used eg the following simple query can find Messages in a folder based on a specific category https://graph.microsoft.com/v1.0/me/messages?filter=Categories/any(a:a+eq+'Green+Category') you can create a SearchFolder based on this query which would search all folder in a Mailbox which would produce...

This is part 2 of my Graph Basic's series and this post is born out of an actual need that I had over the last week which was to get a user photo from the Microsoft Graph and save it as a custom size and different image type. Like many things there are multiple ways of doing this but the Microsoft Graph GetPhoto endpoint  is pretty straight forward and delivers the image in one of the following formats 48x48, 64x64, 96x96, 120x120, 240x240, 360x360, 432x432, 504x504, and 648x648. Because I wanted to use the photo on a Elgato stream deck  this required the size be 72x72 so I needed some extra code to do the resize of the photo and change the format from a jpeg to png. Getting the user-photo from the Microsoft Graph  Before you can get the user's photo from Microsoft Graph you need to make sure the application registration you are using has one of the following permissions User.Read, User.ReadBasic.All, User.Read.All, User.ReadWrite, User.ReadWrite.All Then after you have o...

I haven't done a basics series for a while but based on some of the questions I've been getting lately and the lack of some good Mailbox specific examples for basic but more complex tasks using the Graph against Exchange Online Mailboxes this seemed like a good series to write. For all the scripts in this series I'm not going to use any modules or other libraries so everything will be using Invoke-WebRequest and Invoke-RestMethod, while there is nothing wrong with using libraries or modules and a number of advantages in doing so it just keeps the examples as simple and easy to understand as they can be. Authentication  You can't have an article on the Graph without talking about authentication and we are now far from the past where all you needed was a simple username and password and you where off to the races. The basics of Authentication are is that first you will need an Azure App Registration (that has been consented to), there are many pages dedicated to how you c...

This is part 2 of my blog post on migrating EWS Search to the Graph API, in this part I'm going to be looking at using KQL Searches and using the new Microsoft Search API (currently in Beta). The big advantage these type of searches have over using SearchFilters is that these type of searches use the content indexes which can improve the performance of searches when folder item counts get high. They also allow you to query the contents of  Attachments which are indexed through ifilters on the server. KQL queries on the Mailbox and Mailbox Folders In EWS you have been able to use firstly AQS and now KQL in the FindItems operation from Exchange 2013 up. To migrate these searches to Microsoft Graph is pretty simple eg an EWS FindItem query to search for all messages with a pdf attachment FindItemsResults fiItems = service . FindItems ( QueryFolder , " Attachmentnames:.pdf " , iv ) ; in the Graph you would use something like https: //graph.microsoft.com/v1.0/me/...

This is part one of a two part post where I'm going to look at how you can migrate any searches you are doing in EWS to the Graph API. In this first part I'm going to cover SearchFilters (from EWS) and Search-Folders as they have been around the longest and in part 2 I'll look at Searches which has  some new functionality in beta in the Graph. Lets start by looking at how you might be doing searches in EWS at the moment Search Filters (restrictions) in a FindItem Request that can be run against a Folder or Search Folder QueryString (KQL) in a FindItem Request that can be run against a Folder or Search Folder SearchFolder with a FindItem Request eDiscovery via SearchMailbox which has now been depreciated in Office 365 and no longer supported Search Filters (Restrictions) If you have used the EWS Managed API to build your application you use the SearchFilter class which creates a underlying restriction in EWS https://docs.microsoft.com/en-us/exchange/client-de...

For the last couple of years the most constantly popular post by number of views on this blog has been  Export calendar Items to a CSV file using EWS and Powershell closely followed by the contact exports scripts. It goes to show this is just a perennial issue that exists around Mail servers, I think the first VBS script I wrote to do this type of thing was late 90's against Exchange 5.5 using cdo 1.2. Now it's 2020 and if your running Office365 you should really be using the Microsoft Graph API to do this. So what I've done is create a PowerShell Module (and I made it a one file script for those that are more comfortable with that format) that's a port of the EWS script above that is so popular. This script uses the ADAL library for Modern Authentication (which if you grab the library from the PowerShell gallery will come down with the module). Most EWS properties map one to one with the Graph and the Graph actually provides better information on recurrences then...

A while ago I published this post on accessing the Graph directly from an Arduino, this made use of the "resource owner password credentials grant" (meaning it used a hard coded username and password). Once you have enabled MFA (multi factor authentication) on an account this grant no longer works because you have no ability to provide the other factors for the Authentication to succeed.  For devices like Arduino's or most IOT devices that have very limited UI capabilities this is where device code authentication can be used. The way Device Code Authentication works is instead of posting the user credentials to the token endpoint to get an access token, you make a post first to the /v2.0/devicecode endpoint which will then give you a specific user code to use to authenticate with on another device. You then visit http://microsoft.com/devicelogin (on a pc or mobile device) enter the user code and authenticate as the required user doing any extra MFA authentication. In ...

Calendaring formats in Messaging Clients tend to all follow much the same approach whether its Outlook, Outlook on the Web or Mobile, Gmail or Microsoft Teams .  Like email data, calendar data can be random and complex in its volume and type (recurring appointments etc) so a simple year at a glance calendar for someone designing a mass market client is hard to do well for all the data types and volumes that you could encounter, therefor its not something you see in mail clients by default (lets face it who wants to support that). In the absence of year at a glance calendars  I was surprised to see people using Excel to create yearly aggregated calendars in Microsoft Teams for events (for data that already existed in shared Calendars). But more surprisingly is that it actually kind of worked well when there wasn't a lot of data that needed to be shown. The one thing that sprang to my mind was if you could automate this it  would be really good for people who use the Bir...