Macro to generate PDF's instead generates Excel files

Hi

I recorded a macro to generate a pdf (Excel 2007) to be sent via email. On the recording part, it does what is needed, but when I try run it again, it generates an Excel type file as the attachment!

I tried it on a different computer (also Excel 2007) with same results. Am I missing something?
This is the VB code...

   ActiveWorkbook.ExportAsFixedFormat Type:=xlTypePDF, Filename:= _
       "C:\Users\VANWYN~1\AppData\Local\Temp\testin.pdf", Quality:= _
       xlQualityStandard, IncludeDocProperties:=False, IgnorePrintAreas:=False, _
       OpenAfterPublish:=False
   Application.Dialogs(xlDialogSendMail).Show

Regards,
Shaun