Remote Event Receiver not Canceling and Displaying Exception Message

Question

I created a Remote Event Receiver Provided Hosted Addin and attached it to my Doc Lib for my on-prem environment. RER Event Type is for ItemUpdated. It work as expected. The only problem is I would like to cancel the Event Receiver and display the error message on the SharePoint list page to let the user know there was a problem. Event Receiver is triggered, but exception message is not being displayed, which makes it looks like there are no problems (when there are).

public SPRemoteEventResult ProcessEvent(SPRemoteEventProperties properties) {
    SPRemoteEventResult result = new SPRemoteEventResult();
    try {
        switch (properties.EventType)
        {
            case SPRemoteEventType.ItemUpdated:
                HandleItemUpdated(properties); 
                break;  
        }
        return result;
}
    catch (Exception exception) {
        result.ErrorMessage = exception.Message;
        result.Status = SPRemoteEventServiceStatus.CancelWithError;
        return result;
    }       
}

Not sure what I am missing. How do I make the error message display on the SharePoint page (where properties are updated)?

Answer 1

Can you check and see if the Minimal Download Strategy Site feature is activated by going to Site Settings -> Site features -> Minimal Download Strategy

In case of sites with MDS enabled, there are chances of error message not being displayed as mentioned here