Glen's Exchange and Office 365 Dev Blog

This is a continuation somewhat of my previous post on using a generic oAuth script to access EWS but in this post I'm going to look at how you can authenticate as a Guest user to a tenant you have been granted Guest access to and then access the resources like a Unified Office365 Group or Teams( because Teams uses Groups) via the Graph API. To Access another tenant as a Guest (considering that Guest Access is enabled and you have accepted the invitation and logged in at least once with that user) you need to generate an Access Token against the Target tenants endpoints. To do this you can discover what a particular tenants Authentication and Token endpoints are by making a request like the following $RequestURL = " https://login.windows.net/{0}/.well-known/openid-configuration " - f $TargetDomain $Response = Invoke - WebRequest - Uri $RequestURL $JsonResponse = ConvertFrom - Json $Response . Content This will return a result like the following Out of thi...

Microsoft recently posted an update that will affect those people who use EWS in applications and script against Office365  https://blogs.technet.microsoft.com/exchange/2018/07/03/upcoming-changes-to-exchange-web-services-ews-api-for-office-365   While 2020 is a few years away what this means is that if you are using Basic Authentication in your EWS scripts or applications that on the 13th October 2020 your app will stop working. Given the amount of time you have and the changes required to support oAuth nobody should really be caught out by this but procrastination and people not understanding legacy applications will mean I'm sure this date won't pass without any infamy. Within PowerShell scripts you have two options to generate the oAuth tokens you need to keep you script working. One is to use a dependency library like ADAL to do it which Ingo posted a really good write up for https://ingogegenwarth.wordpress.com/2018/08/02/ews-and-oauth the other is just create some ...

Folder Item numbers, size's and Attachment Item Numbers, types and sizes are one of the Mailbox statistics that is useful when your trying to look at how and why a mailbox is growing or why your mailbox performance might be declining if you have a large number of folder items. With the recent increases in Mailbox size quotas  in Office365 it can be easy to become quite indifferent to how quickly your mailbox might be growing. For example if you have 100GB quota the lazy mindset (which I admit to being a part of) can be to just keep everything you get via mail (or stack it and rack it). If your users are not able to take advantage of cloudy attachments (or the users refuse to change their use habits) the nature of expanding file sizes means a sharper growth curve for Folder Items and Attachments. The traditional way of tracking Mailbox sizes is to use Get-MailboxStatistics and Get-MailboxFolderStatistics for which there are many good scripts around that give a good overview of wha...

Over the years I've created a few different versions of In/Out boards like this that have used Exchange FreeBusy information to present the In/Out status for Users. In this post I am going to look at how you can create the same thing in Microsoft Teams using a Team's tab application that will call some Microsoft Graph endpoints that will first get the members of a particular Team, then there OOF MailTip to determine if they have an AutoResponse set and finally get there userphoto. The end results is a board that looks like this Team's Tab Applications Team's tab apps are very simular to the Add in's framework used across other Office365 products that utilize JavaScript and html to provide a consistent approach across desktop and web clients. However because teams is fairly new the underlying client SDK isn't as feature rich or mature as you would find for example with Exchange/Outlook. Some examples of this is there is no way to get the members of a Team...

Cards are "a user-interface (UI) container for short or related pieces of information ref " which there are currently two formats for, MessageCards and AdativeCards . The underlying data format is a JSON object that describes the content to be rendered by a supporting client. Eg here is a basic sample So they are a simple way of presenting information in consistent manner which  then makes deploying that same UI experience across multiple client forms factors (mobile,web,desktop) a lot easier.  Cards also allow you to define actions, so then the cards themselves can become a small app or part of an integration piece of a Line of Business workflow etc. Actionable Cards in Outlook have the ability to link with an Outlook Addin's see which starts to really extend what you can use cards for. This means your no longer just stuck in the limited feature set of Cards but you can use the richness available in the Outlook Addin framework . Email Security   Cards rel y o...