使用 VBA 和 Outlook 发送 email 时出错

Question

I would like to make an easy automation within excel to send an email from the user form when fulfilled by the user. I have created test code to do so, according to Microsoft how to page. My main problem is visible when I try to use.send (email address swapped to dummy one for the purpose of the question) -

"application-defined or object-defined error".

However when I use.display the message shows up on the screen with no issues. I have added references for Outlook 16 and Office 16, what was suggested in other solutions, and still no positive result. I wonder if that might be an issue related to company policies... but not sure, just wanted to ask for some guidance. Below is the code that was causing the error:

Sub Mail_workbook_Outlook()

    Dim OutApp As Object
    Dim OutMail As Object
    Dim oListObj As Object

    Set OutApp = CreateObject("Outlook.Application")
    Set OutMail = OutApp.CreateItem(0)
    
    email_to = "test.user@test.com"
    email_body = "test 123"
    email_subject = "Test email"
    
    With OutMail
        .To = email_to
        .CC = ""
        .BCC = ""
        .Subject = email_subject
        .Body = email_body
        '.Display
        .Send ' THIS LINE IS CAUSING ERROR FOR ME
    End With

    Set OutMail = Nothing
    Set OutApp = Nothing
    
End Sub

Answer 1

The Send method of the MailItem class is a protected method in the Outlook object model which means it can throw security prompts in Outlook or just give errors when using an unsafe Outlook Application instance. It happens when you try to automate Outlook from external applications. You can find a similar thread which lists possible solutions, see How to avoid the Outlook Security warning for email automation - VBA .

There are several ways for suppressing security prompts/errors in the code:

1. Use a third-party components for suppressing Outlook security warnings. See Security Manager for Microsoft Outlook for more information.

2. Use a low-level API instead of OOM. Or any other third-party wrappers around that API, for example, Redemption.

3. Develop a COM add-in which has access to the trusted Application object.

4. Use group policy objects for setting up machines.

See Outlook Object Model Security Warnings for more information. Also you may find the following articles helpful:

• A program is trying to send an e-mail message on your behalf warning in Outlook
• How to Prevent the VBA Macro Security Warning in Microsoft Outlook