What is KeepAliveTime used for in regards to Exchange?

This one setting has caused more debates and more confusion, and by proxy, more cases than perhaps any other thing in our Exchange Client Connectivity queues since I started working at Microsoft. There is a lot of confusion on what it is actually used for, so I am going to try and clear that up…


How did that 1.5GB message get into my Exchange environment anyway?

ISSUE: Recently, I had a customer call in an issue where their transport services were failing on all Exchange 2013 servers usually within minutes of each other. Transport would restart on its own and then 15 minutes to an hour later, they would crash yet again. The following errors were showing up in the Event…


O365 Migration that completes with warnings due to insufficient rights.

The Problem: With the rise in Hybrid configurations around the world, we are starting to see some regular occurrences of issues around migrating from OnPremises exchange (called OnPrem henceforth) to O365. Perhaps the most common is one where most users migrate fine, but a select few only partially migrate. When you look at the migration logs, they…


No properties available on the Exchange Org container in AD Sites and Services

Scenario: So I ran into an odd case this week where the customer could not see the properties of their Exchange Org container in AD Sites and Services. Not only could they not see it, it’s icon, which should have been a folder icon, was actually the notorious Unknown icon. It looked as such: When…


Shared Free/busy between two untrusted forests failing in one or both directions

In a recent case, I found a pretty common mistake many customers make when setting up their free/busy sharing between two untrusted orgs or more appropriately, when they set up their trusted and intermediate certs for their target domains. Scenario: Contoso and WingTipToys are two partner companies with no forest trust between them that want to…


Unable to expand legacy onPrem Public Folders with O365 account

I have been seeing a few scenarios lately where users who log into Exchange using an account other than the OnPrem User Principal Name (UPN) are running into various difficulties. Today we will focus on one of those scenarios. We will discuss how we figured it out and what needs to be done to get the desired functionality….