Inconsistent behavior of the AppointmentStore API

[TheJoeFin]

Describe the bug

I use the AppointmentStore in my app Ink Calendar to display and edit users' appointments. However in the past year the API has become unstable and unreliable. I have experienced the issue personally and have had users email me upset this feature stopped working.

There are a few failures of the API but the one most important to me is when the AppointmentStore.ShowEditNewAppointmentAsync(Appointment) method returns an empty string instead of a RoamingID of the new appointment. Normally this would mean the user canceled the "Add" but from first hand experience I know this happens even when the new appointment is accepted.

Once the AppointmentStore gets into this error state all of the appointment data becomes stale and does not update. It is unclear why this error state occurs or how to recover the AppointmentStore to get current appointment information from the operating system.

Steps to reproduce the bug

Here is a GitHub repro I made to reproduce this issue.
https://github.com/TheJoeFin/AppointmentStoreReproBug

Expected behavior

AppointmentStore returns up-to-date appointment information for the users' calendars.
AppointmentStore returns a RoamingID when adding a new appointment.

Screenshots

No response

NuGet package version

No response

Packaging type

Packaged (MSIX)

Windows version

Windows 11 (22000), May 2021 Update (19043), October 2020 Update (19042), May 2020 Update (19041), November 2019 Update (18363), May 2019 Update (18362)

IDE

Visual Studio 2022-preview, Visual Studio 2022, Visual Studio 2019

Additional context

This is a UWP API and since it is not open source I do not know the best place to get support on this issue I'm having. I have posted this issue to several other Microsoft Support pages with no success. Please let me know the best place or person to help get this issue resolved.

[TheJoeFin]

Is there any way to get an update on this issue? I'd be happy to connect via email or some other method if that is better for the team. Since my app is a calendar app this API is very important to me.

[michalleptuch]

I've got the same problem - AppointmentStore does not return up-to-date appointments. I need to remove and add again calendar account in Windows settings. It helps but only for a few hours :/

[TheJoeFin]

@michalleptuch I don't think Microsoft will fix this bug, I have been running in to issues for 4 years now and have gotten zero feedback. There are other elements of the appointments API which are broken, but also no response from Microsoft.

[DanieleScipioni]

Would be useful to know the status and the Microsoft's plans about AppointmentStore APIs for UWP and WindowsAppSDK, also considering that Mail and Calendar applications will be dismissed at the end of 2024 (https://support.microsoft.com/en-us/office/outlook-for-windows-the-future-of-mail-calendar-and-people-on-windows-11-715fc27c-e0f4-4652-9174-47faa751b199) and this specific API AppointmentStore.ShowEditNewAppointmentAsync is backed by Calendar.