Announcing the increase of the Public Folder limit in Exchange Online from 250,000 to 500,000 folders

Last September, we officially announced the increase of the supported limit of Public Folders in Exchange Online from 100,000 to 250,000. In line with our efforts to scale Public Folders even further, we are glad to announce that Exchange Online now officially supports public folder hierarchies of up to 500K public folders in the cloud…


Changes coming to the SMTP Authenticated Submission client protocol

There are a number of client protocols offered by Exchange Online to allow email clients to send email from their mailboxes. One of the most widespread protocols is SMTP Authenticated Submission (also known as SMTP Client Submission) which is supported by most email service providers. This non-proprietary protocol is used to send email by legacy…


OffCAT’s replacement – Microsoft Support and Recovery Assistant (SaRA)

After over five years of providing configuration information and solutions to known issues, the OffCAT team is planning to remove OffCAT from the Microsoft Download Center on May 31, 2018. The good news is that core OffCAT features have been consolidated with the Microsoft Support and Recovery Assistant for Office 365 (SaRA) tool at https://diagnostics.outlook.com/….


Office 365: Auto-Expanding Archives FAQ

In recent months we’ve been receiving quite a few questions from customers regarding auto-expanding archives. I’d like to clear up some of the misconceptions and answer some of the most frequently asked questions we get on this subject. Think of this as a FAQ on the subject. Before we get going, I strongly advise folks…


Demystifying Hybrid Free/Busy: Finding errors and troubleshooting

In this second part of the Demystifying Hybrid Free/Busy, we will cover troubleshooting of Hybrid Free/Busy scenarios, more specifically – how and where to find an actual error that will indicate where the problem is. Before venturing forth, please make sure that you have seen Part 1 of this demystifying series! Here is the graphics…


EAI support announcement – Update

In late December 2017, we announced support for EAI in Q1 2018. We are happy to announce that EAI is now enabled in Exchange Online and Exchange Online Protection for Office 365. Office 365 users can now send messages to and receive messages from internationalized email addresses. In addition, we are pleased to announce that…


An Update on Office 365 Requiring TLS 1.2

Hello Exchange Server followers! In December 2017 it was announced Office 365 planned to discontinue support for TLS 1.0 and TLS 1.1 connections on March 1st, 2018, and after that time only TLS 1.2 connections would be allowed when interacting with Office 365. Many of you have been asking for additional detail on what this…


Demystifying Hybrid Free/Busy: what are the moving parts?

Hybrid Free/Busy is one of those things that many people do not fully understand. If everything works well, the complexity is hidden from view and people working in various parts of organization can seamlessly work together. But if things go wrong… you will appreciate deeper understanding of what makes it work. This is why we…


Permanently Clear Previous Mailbox Info

We are introducing a new parameter that can be called by using the Set-User cmdlet in Exchange Online PowerShell. The feature is focused for customers doing migration of on-premises mailboxes to the cloud and you will be able to use it within three weeks or so (Edit 1/19: we updated this due to slower than…


EAI support announcement

Update 2/26/2018: For the latest developments on the subject please see this blog post. Out of 7.6 billion people in the world, only 360 million are native English speakers. Although email has been the earliest and most widely-adopted platform for modern electronic communication, email addresses have only supported a limited subset of Latin characters (mostly…