Tag: Exchange Online

Restrict Azure App Permissions to Specific mailboxes only

With Microsoft disabling basic Authentication starting October 1st 2022, I see a lot of vendors asking us IT Pro’s to create an Azure App registration with mailbox permissions to read out just a single mailbox. However, by default this Azure App grants permissions to every single mailbox in your...

Exchange Online, Basic Authentication end is near…

Microsoft is proactively working on securing their Exchange Online environment. Making your and indirectly other customers environments safer. For now Microsoft is going over all tenants and they will start disabling Basic Authentication. This will include all of the following services: Exchange Web Services (EWS), Exchange ActiveSync (EAS), POP,...

Anti-Spoofing Exchange Online rule (Manual)

Fraudulent emails are becoming a common cyber threat. Anti-spoofing mail rules set up in Office 365 can help. In these phishing schemes, scammers research internal company names and send emails that look like they are coming from the CEO or someone else in the company. Typically the scam emails...

Find inactive mailboxes in Exchange Online

So you want to clean up unused (shared) mailboxes in your Exchange (Online) environment. How to find out which mailboxes have been inactive for a long time? The answer is yet simple again, with a cool Power Shell script. First we will connect to Exchange Online...

Update Exchange Online Global Address List (GAL)

There are situations where you would like to enforce an update of the Exchange Global Address list (GAL) in Office 365. With a few steps this can easily be done! Requirements: Exchange Online EXO V2 module, install using: Import-Module -Name ExchangeOnlineManagement STEP 1: First we will need to make...

Exchange Online: Set default calendar sharing permissions for all users

In a new Exchange (Online) environment you might want to change the default calendar sharing permissions for all users. By default the sharing permissions for the entire organization are set to “Can view when I’m busy”. Some companies have a different wish on the default calendar settings of their...

Change default send items behavior of Auto-mapped Shared Mailboxes

A commonly heart end-user frustration with Auto-mapped shared mailboxes is that Send emails from the shared mailbox end up in the send items of the user it self. In the past you would need to set a registry key on the client computer to get this resolved. But with...

How to solve Failed to sync the ArchiveGuid in Office 365 (Manual)

Last few weeks I’ve been struggling with an very difficult Office 365 / Exchange Online case, that got escalated to multiple Microsoft departments to be fixed. I already found one part of the solution, but Microsoft found the second part. Today I would like to take you through all...