Sub save_a(myItem As Outlook.MailItem)
Dim att_count As Integer
FolderName = "C:\Attachment\" & myItem.SenderEmailAddress & "\"
FullFolder = FolderName & Format(myItem.ReceivedTime, "yyyymmdd") & "\"
If Not Dir(FolderName) <> "" Then
    MkDir (FolderName)
End If
If Not Dir(FullFolder) <> "" Then
    MkDir (FullFolder)
End If
For att_count = 1 To myItem.Attachments.Count
    myItem.Attachments.Item(att_count).SaveAsFile (FullFolder & myItem.Attachments.Item(att_count).FileName)
Next
End Sub