Ok then never mind that
Open the example you uploaded.
Insert in Cell "H3": Type anything that could look like a PO numbe like 12312PONUM2012 - doesn't matter what
then open the VBA Editor and insert a new modul.
And copy this in the new modul: Then try runing the SendEmail Macro

Sub SendEmail()
Dim strFileName As String
Dim strFileLoc As String

    strFileName = ActiveSheet.Range("H3").Value
    strFileLoc = "C:\Files\"
    strBody = "Hi" & vbNewLine & _
              " " & vbNewLine & _
              "You can enter some text here if you want, for file name: " & strFileName & vbNewLine & _
              "And some more text under here :)" & vbNewLine & _
              " " & vbNewLine & _
              "Bye."

    
    ActiveSheet.ExportAsFixedFormat Type:=xlTypePDF, Filename:= _
        strFileLoc & strFileName, Quality:=xlQualityStandard, _
        IncludeDocProperties:=True, IgnorePrintAreas:=False, OpenAfterPublish:= _
        True

Application.ScreenUpdating = 0
    Set ol = CreateObject("Outlook.application")
    Set NewMessage = ol.CreateItem(olMailItem)

With NewMessage
    .To = ""
    .Subject = ""
    .cc = ""
    .attachments.Add strFileLoc & strFileName & ".pdf"
    .body = strBody
    .Display
End With
Application.ScreenUpdating = 1
End Sub