Pdf problem when saving invoices

Hi all - having a problem saving pdf’s of my invoices.
All looks ok on the screen and prints out fine but when I save to a folder on my desktop the image saved is not of a pdf. I have attached a copy of what is saved. I have done a re-boot (ever hopeful!) but problem still seems to be there. I can create pdf’s on my pc from other documents but the ones created in Quickfile don’t seem to be working. Any help would be gratefully received.

I don’t think this is an issue with the way Quick File is delivering the PDF, it looks like some local software problem interpreting PDFs on your machine. Try installing the latest version of Adobe Reader.

Thank you Glenn, problem solved!