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OT: Back online


Just a quick post to say im back online after a good holiday im still trying to catch up on everything. This is one of the more amusing signs that I came across while on holidays.

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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
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Sending a Message in Exchange Online via REST from an Arduino MKR1000

This is part 2 of my MKR1000 article, in this previous post  I looked at sending a Message via EWS using Basic Authentication.  In this Post I'll look at using the new Outlook REST API  which requires using OAuth authentication to get an Access Token. The prerequisites for this sketch are the same as in the other post with the addition of the ArduinoJson library  https://github.com/bblanchon/ArduinoJson  which is used to parse the Authentication Results to extract the Access Token. Also the SSL certificates for the login.windows.net  and outlook.office365.com need to be uploaded to the devices using the wifi101 Firmware updater. To use Token Authentication you need to register an Application in Azure https://msdn.microsoft.com/en-us/office/office365/howto/add-common-consent-manually  with the Mail.Send permission. The application should be a Native Client app that use the Out of Band Callback urn:ietf:wg:oauth:2.0:oob. You need to authorize it in you tenant (eg build a small ap
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How to test SMTP using Opportunistic TLS with Powershell and grab the public certificate a SMTP server is using

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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.

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