在VBscript中使用CDO.Message-无法发送二进制附件

Question

发送带有文本文件的电子邮件，可以正常工作（收到测试电子邮件）：

Set emailObj = CreateObject("CDO.Message")
emailObj.From = "sender@domain.tld"
emailObj.To = "recipient@domain.tld"
emailObj.Subject = "File attached" 
emailObj.TextBody = "Please have a look at the attached file. Thanks."
emailObj.AddAttachment "d:\temp\test.txt"

Set emailConfig = emailObj.Configuration
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/smtpserver") = "server.webhost.com"
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/smtpserverport") = 465
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/sendusing") = 2  
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate") = 1  
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/smtpusessl") = true 
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/sendusername") = "sender@domain.tld"
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/sendpassword") = "top_secret"
emailConfig.Fields.Update

emailObj.Send

If err.number = 0 then Msgbox "Your file has been sent. Someone will respond as soon as possible."

但是，当我尝试发送二进制文件时，这不起作用（未收到测试电子邮件）：

Set emailObj = CreateObject("CDO.Message")
emailObj.From = "sender@domain.tld"
emailObj.To = "recipient@domain.tld"
emailObj.Subject = "File attached" 
emailObj.TextBody = "Please have a look at the attached file. Thanks."
emailObj.AddAttachment "d:\temp\test.rtf"

Set emailConfig = emailObj.Configuration
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/smtpserver") = "server.webhost.com"
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/smtpserverport") = 465
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/sendusing") = 2  
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate") = 1  
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/smtpusessl") = true 
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/sendusername") = "sender@domain.tld"
emailConfig.Fields("http://schemas.microsoft.com/cdo/configuration/sendpassword") = "top_secret"
emailConfig.Fields.Update

emailObj.Send

If err.number = 0 then Msgbox "Your file has been sent. Someone will respond as soon as possible."

我需要添加/更改什么才能附加二进制文件？