we are developing an app for outlook using Apps for Office JavaScript API. We need to be able to store properties for each appointment per user, but the appointments may or may not reside in the logged-in user's calendar. they may instead be in a shared calendar that the user has been granted read/write access.
However, when using the loadCustomPropertiesAsync method of the opened item, it fails if the appointment is from a shared calendar.
We attempted to work around this by using the roamingSettings object, but it appears these properties are not per message (like custom Properties are) but rather GLOBAL to the application, so no matter what message they open it will always have the same properties.
Is there any workaround to this? users want to be able to utilize the compose app but need to be able to use it with shared calendars.
I cross posted this on the Apps for Office 2013 forum on MSDN and it appears that the current version of the API (1.1) simply does not support custom fields for shared calendars, and there is no known workaround.
If you require this feature yourself, please upvote this request in UserVoice for the feature: http://officespdev.uservoice.com/forums/224641-general/suggestions/8013672-appointment-api-does-not-support-multiple-shared