Smart Alerts OnMessageSend Classic Outlook Windows - taskpane doesn't open if errorMessage is not set

[alexm-plutoflume]

Provide required information needed to triage your issue

There is an issue in Classic Outlook on Windows such that even with commandId set, the taskpane does not open when clicking 'Don't Send' if the errorMessage property is not set when calling eventCompleted. Additionally, the cancelLabel property is not adhered to if errorMessage is not set.

In all other platforms (OWA, Mac, New Outlook for Windows) the task pane will open even if errorMessage is not set, and the cancelLabel property appropriately changes the 'Don't Send' button label even if errorMessage is not set.

The documentation does not indicate that errorMessage needs to be set to open the task pane.

Your Environment

Classic Outlook for Windows - Version 2411 Build 16.0.18227.20162 64-bit
Windows Version: Windows 11 23H2 Build 22631.4602

Expected behavior

If commandId is specified but errorMessage is not when calling eventCompleted, the taskpane should still open.
Additionally, if cancelLabel is set but errorMessage is not, the cancelLabel should still be adhered to.

Current behavior

For Classic Outlook on Windows, if errorMessage is not set when calling eventCompleted, the task pane won't open and the Don't Send button also can't be renamed using the cancelLabel property.

This works correctly in all other platforms.

Steps to reproduce

1. Have an OnMessageSend smart alerts addin that supports opening a task pane.
2. Don't allow an email to send and set commandId specifying the task pane to open and cancelLabel to something to rename the 'Don't Send' button.
3. Send an email that will be blocked.

Note that the 'Don't Send' button didn't change labels, and that clicking 'Don't Send' doesn't open the task pane.

Then perform the same steps but ensure errorMessage is set. Note that the label changes and you can open the task pane.

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[github-actions]

Here are some similar issues that might help you. Please check if they can solve your problem.

• Smart Alert Feature not working in Outlook Mac Thick Client  #4608

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Possible solution (Extracted from existing issue, might be incorrect; please verify carefully)

Solution 1:

This is the expected behaviour for the SoftBlock send mode. Please find details here - https://learn.microsoft.com/en-us/office/dev/add-ins/outlook/onmessagesend-onappointmentsend-events?tabs=mac . You can use the PromptUser mode in your add-in, but in this case in Offline mode the add-in does not run at all, and the email will go to Outbox without showing any alert.

Reference:

• Smart Alert Feature not working in Outlook Mac Thick Client  #4608 (comment)

Solution 2:

After further review, this feature is not behaving as originally designed, the disconnected [do not confuse with 'work offline' feature] experience in smart alerts need to include a 'send anyway' option for PromptUser and SoftBlock Modes, the team will work on enabling this.

Reference:

• Smart Alert Feature not working in Outlook Mac Thick Client  #4608 (comment)

[alexm-plutoflume]

None of those possible solutions are related

[millerds]

Thank you for reporting this bug. I have logged an internal tracking item for this (id: 9684299) for follow up. Unfortunately, we cannot comment on potential timelines for a fix. In the meantime, you can always just set the errorMessage property to get the desired behavior.