Acrobat and Reader Version Issues

Hi,

I've created a PDF porffolio made up of several PDFs. When I view the PDF portfolio at the "top level" (where you see names of the individual PDFs on top of a window that looks like it should show the first page of the PDF) all it says in the window is "For the best experience, open this PDF porffolio in Acrobat X or Adobe Reader X, or later. However, I have Acrobat XI and am viewing it in Acrobat XI, so why am I having this issue?

I can at least open the PDF portfolio and all the PDFs inside. My girlfriend gets the same window when I try sending it to her and can't open the PDF portfolio at all andl she has Acrobat 11.0.3. Why is this happening to her?

Attached is a screenshot of my issue.

Thanks.