另存为工作簿类的方法失败 - Outlook vba

Question

我试图用xlsx文件格式保存outlook邮件附件文件（单个文件）但在Save as Mehtode of workbook class failed行下面显示错误wb.saveAs的代码。需要别人的帮助。

 Public Sub saveAttachtoDisk(itm As Outlook.MailItem)
        Dim objAtt As Outlook.Attachment
        Dim objExcel As Object
        Dim wb As Object
        Dim saveFolder As String, dateFormat As String, fName As String
        saveFolder = "D:AshokWorkCapitalCollection"

        For Each objAtt In itm.Attachments
        sFileName = LCase(objAtt.FileName)

            sPathName = saveFolder & sFileName
            objAtt.SaveAsFile sPathName


    Set objExcel = CreateObject("Excel.Application")
            Set wb = objExcel.Workbooks.Open(sPathName)

' error on below line

            wb.SaveAs FileName:=Replace(sPathName, ".csv", ".xlsx"), FileFormat:=xlOpenXMLWorkbook 
                wb.Close SaveChanges:=True


            Kill sPathName
            objExcel.Quit

    Next
    End Sub