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c#comvstooffice-interopoutlook-addin

Outlook VSTO - Update Periodic AppointmentItem Parent

I'm working on an Outlook Add-In (plugin) and I'm basically working with Outlook appointment items (Outlook.AppointmentItem).

Each time someone create, save or update an occurrence of a periodic appointment item, i need to get the main AppointmentItem (the parent) and add or update an UserProperty.

Until here, it's more or less working. That means i get the parent and i can manipulate his UserProperties but it doesn't work every time.

If the periodic appointment has 5 occurrences and for each references i update something, I'm expecting to modify the UserProperties of the parent 5 times. But that doesn't work and sometimes the parent his old "state".

Technically, in the Item_Write I get the parent and change his UserProperties. And just before the last bracket of the Item_Write i check the UserProperties of the parent and they contain what I'm expecting. But in the "Close" method who is called just after the Item_Write when i check if the parent still contain the expected UserProperties I see that they haven't been updated and they still are in the same state that before.

After some research, i saw a lot of people (even the Msdn) saying that i should use Marshal.ReleaseComObject(). I tried that and now I'm releasing the parent (and other COM object) every time i call them. Maybe I'm not using it well and because of that, it's still doesn't work.

The problem seems to appear between the Item_Write and the Close. After leaving Item_Write the UserProperties are okay, but when i enter the Close they are not anymore. Does anyone ever have any similar problem?

Should i use Marshal.FinalReleaseComObject() on the parent just before the end of Item_Write?

I you think it's better or it will be easier to understand what's going on by looking at some part of my code, just ask.

Solution

  • This sounds like it is most definitely related to not properly releasing objects. Read the Remarks section in the documentation for the AppointmentItem.GetRecurrencePattern method as it describes your situation perfectly: https://msdn.microsoft.com/en-us/library/office/ff868441.aspx.