New Mail Event does not work with some delegate mailboxes

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New Mail Event does not work with some delegate mailboxes
 
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wehbi




Posts: 81
 Joined: 2013-10-31
Dear Add-In Express Team,

One of our customers is experiencing an issue where the "New Mail" event does not fire when using delegate mailboxes. What makes this particularly puzzling is that other delegate mailboxes on the same system are working as expected.

The following events are being used but are not triggered:

-public void adxOutlookEvents_NewMailEx(object sender, string entryIDCollection)
-public override void ItemAdd(object item, object sourceFolder)

The customer is running Exchange On-Premises version 0.20 (15.0.0.0) and the latest Outlook client.

Is there a known solution or recommended approach to resolve this issue?

Thank you in advance.

Best regards,
Birger
Posted 02 Dec, 2025 07:28:51 Top
Andrei Smolin


Add-in Express team


Posts: 19182
 Joined: 2006-05-11
Hello Birger,

Find an example at https://www.add-in-express.com/creating-addins-blog/outlook-newmail-custom-solution/. It deals with the NewMail/NewMailEx events not occurring for some or all emails received. It also deals with the "emails received while Outlook was closed" scenario.

Regards from Poland (GMT+1),

Andrei Smolin
Add-in Express Team Leader
Posted 02 Dec, 2025 09:57:17 Top