method Attachment.Save ([FileName as Variant])
Saves the attachment to a file.

TypeDescription
FileName as Variant A string expression that defines the name of the file to create and save the attachment's data. If no FileName parameter is provided, the Save saves the data using the attachment's name under the current directory. 
The Save method saves the data of the attachment to a file. The Name property specifies the name of the attachment. Please be aware that providing no FileName, indicates that the Save method saves the data using the attachment's name under the current directory. The Data property returns the data of the attachment as a safe array of bytes.

The following sample saves all attachments) into the c:\temp folder:

With ibx
    Dim iMessage As Long
    For iMessage = 0 To .Count - 1
        With .Item(iMessage)
            Dim iAttachement As Long
            For iAttachement = 0 To .AttachmentsCount - 1
                With .Attachment(iAttachement)
                    .Save "c:\temp\" & iMessage & "." & .Name
                End With
            Next
        End With
    Next
End With

The file name of each attachment is prefixed by  the message's index (0-based), succeeded by the attachment's name such as : 12.image01.png