Exchange Server

Latest Articles

Use Azure Front Door to Leverage Microsoft’s Global Network for Exchange

With Azure Front Door, you can reduce the strain on Exchange through caching, content compression, and by filtering out malicious bots before traffic even hits the on-premises network. In this article, we demonstrate how you can use Front Door to reduce your Exchange Server load, increase OWA Client performance and provide Microsoft managed certificates.

March 1, 2022

The Practical 365 Update – Episode 34: Why we still need to talk about Exchange

For the first episode of 2022, Paul Robichaux and I didn't think we'd still be talking about Microsoft Exchange. But, here we are - as with the new year, new problems in Exchange On-Premises greeted Exchange admins. On the show this week we discuss Y2K22 first, and then take a deep dive into why 2022 is beginning, yet again, with Exchange On-Premises issues.

January 7, 2022

Engineering Snafu Causes Mail Delays for Exchange Server

A version checking problem for malware engine signature files caused on-premises Exchange servers to fail to process inbound email. The issue appears to be due to a date validation problem caused when the checking routine couldn't deal with 2022 when the new year rolled around. Microsoft fixed the problem, but the issue poses questions about Microsoft's commitment to on-premises Exchange Server.

January 2, 2022

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

Researcher Says Autodiscover Problem is Client-Side, Not in Exchange

An interesting and worthwhile interview (available on YouTube) with security researcher Amit Serper reveals a lot more detail about the Autodiscover credential leak reported by Guardicore last month. The interview (with three Office 365 MVPs) goes through the collection of leaked credentials, how Serper tried to reproduce the problem, and his interaction with Microsoft. It’s a real pity Serper didn’t include the information in his original report as it would have taken a lot of heat out of the situation.

October 12, 2021

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

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