March 2020 significant update to Hybrid Configuration Wizard
Published Mar 19 2020 09:21 AM 42.4K Views

(Post updated on 3/26/2020 to add more information about installation process)

We wanted to let you know that we are releasing what we consider a significant update to Exchange Hybrid Configuration Wizard (HCW). Along with a handful of small bug fixes, there are four major changes coming that we wanted to share with you:

  1. HCW will no longer enable Federation Trust by default for all installations. Instead, it will only enable Federation Trust if there are Exchange 2010 servers on premises. HCW will call Get-ExchangeServer and if no Exchange 2010 servers are reported, the workflow to enable Federation Trust and subsequently require domain proof will not execute. Note that organization relationships are still created.
  2. When uninstalling the hybrid agent and switching to Classic in the HCW, this action would sometimes fail with a “null reference” error. We have fixed this!
  3. How many of you have hit the HCW 8064 error – unable to configure OAuth, and subsequently had no idea why OAuth failed to configure? Yes, we heard you loud and clear! In this release, we have completely changed the way we enable and configure OAuth. Instead of enabling OAuth at the service layer, we now enable OAuth via a Graph API under the context of the Tenant Admin. This in turn removes the error obfuscation we had with the service layer enablement and allows us to include a detailed error entry in the HCW log. So while you still see the HCW 8064 error in the HCW UI, you can now review the log for the specific error detail which will make it easier to troubleshoot and resolve.
  4. When verifying DNS, we had a fallback mechanism that would reach out to an external site to verify domains. While this fallback mechanism was rarely hit, we received overwhelming feedback to not use this mechanism/site as it was not listed in our IPs & URLs web page. We have removed that fallback and now only use the endpoint “”, which is listed in our endpoints documentation.

Because this is a major version update, the build begins with 17.x vs 16.x. The build number can be found in the top right corner once you download and open the HCW.

Because of the web-based distribution nature HCW uses and this version is a brand new package, you will get all this goodness simply by installing the new HCW from here. The current builds of HCW (16.x) will not automatically update to 17.x build, in fact – you could run the two side-by-side. Once you are on 17.x build – the HCW will then auto-update as usual.

A few additional notes: At this time, we do not anticipate new HCW 16.x builds. Therefore, to continue getting new HCW builds in the future, uninstall the current version of HCW (16.x) and then install the new version (17.x). The new version of HCW has a new dependency, .NET 4.7.2. The installer should take care of this for you, but just so you are aware.

On installation of the new version of HCW

Generally speaking, the HCW is a standalone, stateless app that gathers configuration information and applies the necessary changes to get to your topology into the desired state. These changes are applied at the Exchange Organization level (both on premises and in the cloud/tenant configuration). Those settings are not stored or managed by the HCW after the run has completed. The Hybrid Agent, once installed and configured runs on the specified machine and is also not tied to the HCW app after installation completes.

Unless you need to re-run HCW, there is actually no need to uninstall and reinstall the new version. In fact, once hybrid is configured, the HCW itself could be uninstalled and it would have no effect on the hybrid configuration it deployed.

In case that at some time you want to re-run HCW, you would want to run the latest version… and that is why we mentioned that you should uninstall the 16.x version and install the 17.x version. But if you do not plan to re-run HCW, you do not need to actually do anything.

Exchange Hybrid Team

Version history
Last update:
‎Mar 26 2020 07:02 AM
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