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Add-MailboxFolderPermission -Identity "UserName:\inbox\Calendar2" -user USERNAME -AccessRights Owner
Add-MailboxFolderPermission -Identity "UserName:\inbox" -user USERNAME -AccessRights FolderVisible
Add-MailboxFolderPermission -Identity "UserName" -user USERNAME -AccessRights FolderVisible
This opens the Open Other User's Folder dialog box, as shown in the following screen shot. Type the LegacyExchangeDN value for the hidden mailbox from which to open a shared folder.
4) Try accessing shared calendar in outlook using legacyexchangedn
