This is just a quick post that is meant to help people out who are having some issues with creating a Hybrid Configuration with Office 365 and Exchange 2010 SP3. There are some serious bumps in the road that you can come across when setting this up that may cause you to spend countless hours troubleshooting without any real success. I’ll elaborate on a couple of the problems that I’ve run into here, and follow up with the solution that worked for me with these issues at the end of the post.
AutoDiscover Failures and Free/Busy Issues
One of the things that you may run into after completing is AutoDiscover failures. You’ll know you have this problem when a cloud (or on-prem) user can log into OWA, but cannot set up their mailbox in Outlook or through Activesync. This can also present in an unusual fashion when you attempt to look up cross-premises Calendar information. Cross-premises calendar sharing utilizes the Exchange Federated Sharing features of Exchange, and this in turn utilizes Autodiscover to work properly. If you can’t view calendars in either direction (from On-Prem to Cloud or Cloud to On-Prem), and you get an error that the Free/Busy information couldn’t be read, look into Autodiscover first.
Generally, there isn’t a whole lot you can do to resolve Autodiscover errors, since Autodiscover is something that you have some pretty limited control over. Microsoft Recommends that the Autodiscover.company.com record that you publish in your Public DNS, so you shouldn’t have to change your Autodiscover record when introducing a Hybrid configuration. Unfortunately, there isn’t much more you can actually do once the Records are configured.
There is, however, a tool you can use to help you troubleshoot some issues with Autodiscover and Office 365 in a hybrid environment. Since Autodiscover is required for Free/Busy exchange to function, it may actually be possible to resolve your error by using Microsoft’s Free/Busy error troubleshooting tool. It’s available here: http://support.microsoft.com/kb/2555008
If you aren’t experiencing Free/Busy errors, the tool may not be as handy, but I suggest trying to go through it a bit anyway, since it can give you some tips for resolving Autodiscover errors. If you have on-prem users that are having trouble configuring clients with autodiscover, tell the tool you have on-prem users that can’t see free-busy for Cloud users. If you have cloud users that are having trouble, do the opposite. If neither are working, use the other option available in the tool.
What Solved My Problem
Interestingly, it took me about 2 or 3 days of digging before I finally found the solution to my autodiscover and free/busy issues. It turned out that my problems were caused by some information that Microsoft failed to let anyone know about.
When you run the Hybrid Configuration tool, it will make some major changes to each of the CAS and HUB servers that you add as Hybrid Endpoints. However, because the hybrid configuration wizard actually makes these changes remotely and on demand, it does not actually complete the setup for you. Once you complete the Hybrid Configuration Wizard and add *any* CAS or HUB servers as hybrid endpoints (All your CAS and HUB servers should be hybrid endpoints for optimum functionality), *make sure to reboot those servers*. The changes that are made by the Hybrid Configuration wizard *will not* apply fully until the World Wide Web Publishing Services and IIS services are restarted. You can achieve the same goal by running IISRESET on your CAS/HUB servers like I did if you are in a situation where rebooting will create unnecessary downtime, but a full reset is a good idea.