"In this blog post Exchange Server MVP Michael Van Horenbeeck and Office 365 MVP Loryan Strant will attempt to bridge the divide between the on-premises world and the cloud – and why sometimes it doesn’t always work as we expect.
A great feature of Exchange Server 2010 and 2013 is the ability to share calendar Free/Busy information with users outside of your organisation. This is also the case with Office 365 – and in fact is even easier for users to do.
However in the situation of a hybrid between Exchange Server and Exchange Online there can be a very small caveat that can cause confusion."
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