Glen's Exchange and Office 365 Dev Blog

Microsoft have annouced they will be restricting access to Microsoft Teams data via EWS from the 30th September see https://devblogs.microsoft.com/microsoft365dev/restricted-access-to-microsoft-teams-data-via-ews-starts-september-30-2022/ . If you are using EWS to access any teams data you will need to move to the Graph API's https://docs.microsoft.com/en-us/microsoftteams/export-teams-content one thing to note is "Microsoft Teams APIs in Microsoft Graph that access sensitive data are considered protected APIs" so there are some extra steps and time you need to access this data and be aware of the potential need to pay for that access eg "On July 5th 2022, metered consumption is active, and will be billed through an Azure subscription" ref https://practical365.com/teams-export-graph-apis/.

With the full depreciation of Basic Authentication around the corner I've put together a Github doc to show one implementation of using MSAL with the EWS Managed API that supports both Hybrid Modern Authentication and token caching and refresh. It can be found  https://github.com/gscales/EWS-BasicToOAuth-Info/blob/main/EWA%20Managed%20API%20MASL%20Token%20Refresh.md

Sending a message with a large attachment used to be the least worst option when it came to shipping data between people. In the Modern workplace where document and file sharing options are a lot better sending email with a large attachment can tends now to be the worst option especially when it comes to version control, expiration etc. However if you do find yourself with the need to send an email with large attachments (larger then 4MB) and you want to make use of the Microsft Graph API then it requires you use a different method from just sending the message in one post eg  https://docs.microsoft.com/en-us/graph/outlook-large-attachments?tabs=http This does make sending a Message a lot more complex eg if you have a Message less the 4MB you can just make one REST Post to send that message. If you have a large attachment you then have a multi step process eg Create a Draft message where you set all the other message property eg Subject,To,Body Take the MessageId(graph item id) returne

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 Graph

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