To get the OWA path directly to your desired folder you just have to assemble a URL that includes all of the hierarchy. If it is in All Public Folders\Subfolder\Other Subfolder\Calendars\Office then the path in OWA should be http://owa.company.com/Public/Subfolder/Other%20Subfolder/Calendars/Office. Use %20 to replace any spaces. Other non-alphanumeric characters may also need to be substituted. And obviously replace owa.company.com with your normal OWA server address.
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