Stale Mail Category Outlook VSTO

Question

I am trying to modify a Mailitem's category. First, I set

mail.Categories = ""; mail.Save();

Then at some later point, I set the following:

mail.Categories = "Red Category"; mail.Save();

This works most of the time, but sometimes the old category is stale in the messages pane, while the category displayed in the message is correct. If I right-click, only the Red Category is applied as it should. Is there a reason I am experiencing this inconsistency?

Does it work if you select a different message and the select the problematic one again? — Dmitry Streblechenko
No, it does not. It is only resolved if I close Outlook and re-open. This seems to only happen on emails I've copied over from an IMAP account and dropped into this Exchange account. — jkamdjou
That means Outlook is caching he messages. Where does mail variable come from? Do you always release it as soon as you are done using Marshal.ReleaseComObject? — Dmitry Streblechenko

Eugene Astafiev Eugene Astafiev · Accepted Answer · 2018-05-13T07:55:48

Sometimes you need to refresh the view in Outlook by switching to another folder or re-opening an inspector window if you make changes through the Outlook object model.

For explorer windows you may set the CurrentFolder which allows to set a Folder object that represents the current folder displayed in the explorer.

For inspector windows you may close it, release the item shown in the inspector window and then re-open an item by using the EntryID value. See the NameSpace.GetItemFromID method which returns a Microsoft Outlook item identified by the specified entry ID (if valid). Sometimes just re-opening an inspector window helps.

Stale Mail Category Outlook VSTO

1 Answers