Shared Calendar Shortcuts eg are an Outlook and OWA feature that can be handy to automate if you need to deploy a number of these to new (or existing) mailboxes and you don't want to go through the invitation/accept procedure or manually adding each shortcut. While there are no supported operations in EWS for creating these type of objects, it can be achieved by setting the Extended MAPI properties that constitute the shortcut. The downside of this is that it wouldn't ever be considered supported if it all goes horribly wrong. The properties involved in the shortcut are documented in the following protocol document http://msdn.microsoft.com/en-us/library/ee157359(v=exchg.80).aspx . For a couple of these properties the values you need to get can't be obtained directly in EWS so some others tricks are needed. The PidTagWlinkAddressBookEID property contains the MAPI address Book EntryId for the shared Calendar your connecting to. The Address Book EntryID format is...
Pushing the Envelope in Messaging and Office 365 Development