you are almost there. Go back into resources and rename WBENCCertificat2010 to be WBENCCertificat2010_pdf (remember this is how you will be able to know what type of file it is so you can append the correct extension on it to write it out to a temp file. Then when you launch the file, the extension will tell windows what app to open it with, adobe, word, etc..)

so when you add the file to the resources, you will need to add _pdf or _doc, or whatever the correct extension is, to the resource name itself. Then it should work.