Glen's Exchange and Office 365 Dev Blog

One of the email UI features that I find the most useful in Outlook on the Web and Outlook mobile is the People favorites feature which saves having to do a search for historical email from particular high use contacts. Favorites is a feature that has evolved especially in Outlook on the web and Outlook mobile eg People/Persona favorites and category favorites. The way this is implemented in the Mailbox is interesting eg   People/Persona favorites get their own search folder under the favoritePersonas Folder in the Non_IPM_Subtree in a Mailbox eg As well as a configuration object under the  \ApplicationDataRoot\32d4b5e5-7d33-4e7f-b073-f8cffbbb47a1\outlookfavorites eg The configuration object is of interest as this tells as a lot about what type of favorites are being created and used in a Mailbox. It also can serve in a custom app if you want to reproduce the same type of favorites folder tree (you will need to use EWS for this as the Graph API is unfortunately hamstrung ...

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...

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 Gr...

A while ago I published this blog post about doing this using EWS and a few people have recently asked if it is also possible to do this with the Graph API(which it is) so I've decided to include this one in my Graph Basics series. Moderation Moderation is an Exchange feature that was introduced in Exchange 2010 that allows the Human control of mail flow to a distribution group or mailbox see  https://docs.microsoft.com/en-us/exchange/security-and-compliance/mail-flow-rules/manage-message-approval  for more detail. Moderation Approve/Reject Messages When a Message is requiring moderation an email is sent to one (or more) moderators requesting approval. In the Graph you can get these moderation messages by filtering on the MessageClass property. Because this isn't a first-class property like it was in EWS you need to use the singleValueExtendedProperties representation of the property. eg in the Graph a Request like this https : //graph.microsoft.com/v1.0/me/mailFolders('I...

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-re...

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...