Office 2016 中的 MailItem.GetInspector.WordEditor 生成应用程序定义或对象定义的错误

csharp
using Outlook = Microsoft.Office.Interop.Outlook;
using Word = Microsoft.Office.Interop.Word;
public void EditMailBody(Outlook.MailItem mailItem)
{
    Outlook.Inspector inspector = mailItem.GetInspector;
    Word.Document wordDoc = inspector.WordEditor as Word.Document;
    
    if (wordDoc != null)
    {
        // 在邮件正文中插入文本
        wordDoc.Content.Text = "这是一封测试邮件";
        
        // 格式化邮件正文
        wordDoc.Content.Font.Size = 12;
        wordDoc.Content.Font.Bold = true;
        
        // 保存并关闭Word编辑器
        wordDoc.Save();
        wordDoc.Close();
    }
}