Exchange Online

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Exchange Online Introduces DANE and DNSSEC for Outbound Email 10 Comments

Exchange Online Introduces DANE and DNSSEC for Outbound Email

In a December 24 announcement, Microsoft says that the roll-out of DNSSEC and DANE support in Exchange Online will start in mid-January 2022. Because this is a big change for the Exchange Online infrastructure, Microsoft is using a phased deployment which won't complete until mid-May. Support for DNSSEC and DANE has been coming for a long time, but it's good that the extra security which these standards bring will be available to Exchange Online tenants.

January 17, 2022
Separating users in Office 365 using Address Book Policies 10 Comments

Separating users in Office 365 using Address Book Policies

Microsoft 365 has many built-in controls to manage how users communicate externally, however, these controls do not generally extend to internal communication. While this is fine in most environments, situations exist where a degree of separation is required to segregate communication across different groups of users. This article details the configuration of Address Book Policies, and how they can be extended to include Teams.

January 5, 2022
Can Azure AD Custom Security Attributes Replace Exchange Custom Attributes? 9 Comments

Can Azure AD Custom Security Attributes Replace Exchange Custom Attributes?

Microsoft launched the preview of Azure AD custom security attributes on December 1. Custom attributes are well known to Exchange administrators. In this article, we look at how to create and add Azure AD custom security attributes, how to transfer data from Exchange to Azure AD, and how to retrieve information from the attributes. Azure AD custom security attributes have some advantages, but they also have some downsides.

January 4, 2022
Ignite 2021 is Next Week. Here’s What I Anticipate for Microsoft 365 4 Comments

Ignite 2021 is Next Week. Here’s What I Anticipate for Microsoft 365

Microsoft Ignite 2021 happens (virtually) on Nov 2-4. There are tons of sessions scheduled and in this post we consider some important Microsoft 365 topics that we hope Microsoft will cover to help technologists plan tenant development over the coming year. Above all, we're looking forward to being able to attend conferences like Ignite in person so that we can learn from experts from inside and outside Microsoft.

October 26, 2021
Send Exchange Online Email Using the Microsoft Graph SDK for PowerShell 16 Comments

Send Exchange Online Email Using the Microsoft Graph SDK for PowerShell

Many people use the PowerShell Send-MailMessage cmdlet to send email from Exchange Online. In this article, we explain how to use cmdlets from the Microsoft Graph SDK for PowerShell to do the same job. The reason why this is important is that Microsoft will eventually deprecate the Send-MailMessage cmdlet as part of its campaign to eliminate basic authentication from Exchange Online. A replacement will be needed for all those PowerShell scripts which uses Send-MailMessage. This is one solution.

October 18, 2021
Time to Move Off Exchange Online DLP Policies 8 Comments

Time to Move Off Exchange Online DLP Policies

Microsoft plans to remove the management of Exchange transport-rule based policies from the classic EAC in mid-2022. Given that Microsoft 365 DLP policies offer the same if not better functionality for Exchange Online and can process other workloads as well, it's a good time to consider transitioning away from the older technology. Microsoft is obviously not putting any engineering effort into Exchange-based DLP, so there's no good reason not to move over and use the technology they are investing in, The transition will take time and effort, but it will be worth it.

October 8, 2021
Microsoft Caps Exchange Online’s “Unlimited Archive” at 1.5 TB 19 Comments

Microsoft Caps Exchange Online’s “Unlimited Archive” at 1.5 TB

On November 1, Microsoft will limit auto-expanding archives to 1.5 TB and bring the era of "bottomless archiving" to an end. The new limit might not affect many Exchange Online tenants, but it's a wake-up call for administrators to check how archiving is used in their tenants. To help the process, we've written a PowerShell script to report the current set of user and shared mailboxes with archives.

September 29, 2021
Why a Potential Autodiscover Flaw is Just the Tip of an Iceberg

Why a Potential Autodiscover Flaw is Just the Tip of an Iceberg

It's often helpful when security researchers like Guardicore shed light on flaws in Microsoft Exchange - however, the Autodiscover protocol isn't flawed in the way they describe. Even though the issue is hard to replicate, it shouldn't distract from the work you need to do to protect your organization from the underlying reason why people want your credentials.

September 28, 2021
Hot Air and Publicity for Purported Autodiscover Security Flaw 13 Comments

Hot Air and Publicity for Purported Autodiscover Security Flaw

Lots of excitement was generated when Guardicore revealed a purported vulnerability with the Exchange Autodiscover service. However, the almost total lack of detail about the configuration used for testing and to generate the reported results makes it impossible for Exchange administrators to check the theory against their own deployment. I don't think a problem exists with Exchange Online, but it's possible that poor DNS practice or flawed third-party clients could cause an issue with on-premises servers. The case remains to be proved.

September 23, 2021