VBA Outlook Restrict返回"nothing“

Sub FilterUnreadEmails()
    Dim OutlookApp As Outlook.Application
    Dim OutlookNamespace As Outlook.Namespace
    Dim Inbox As Outlook.MAPIFolder
    Dim UnreadEmails As Outlook.Items
    Dim FilteredEmails As Outlook.Items
    Dim Email As Outlook.MailItem
    
    ' 创建Outlook应用程序对象
    Set OutlookApp = New Outlook.Application
    ' 获取Outlook命名空间
    Set OutlookNamespace = OutlookApp.GetNamespace("MAPI")
    ' 获取收件箱文件夹
    Set Inbox = OutlookNamespace.GetDefaultFolder(olFolderInbox)
    ' 获取所有未读的邮件项
    Set UnreadEmails = Inbox.Items.Restrict("[Unread] = True")
    
    ' 遍历筛选出的未读邮件
    For Each Email In UnreadEmails
        ' 在此处处理邮件项，例如打印主题
        Debug.Print Email.Subject
    Next Email
    
    ' 释放对象
    Set Email = Nothing
    Set FilteredEmails = Nothing
    Set UnreadEmails = Nothing
    Set Inbox = Nothing
    Set OutlookNamespace = Nothing
    Set OutlookApp = Nothing
End Sub