I had 9.5 installed as well, so I had to go to the Edit | Preferences | General Tab in XI, select Set Default PDF Handler and then selected Adobe Acrobat Pro 9.5, clicked apply and waited for Acrobat Pro 9.5 to re-install. I was then able to embed Acrobat
files in Office 2010 32b without issue. When back to theEdit | Preferences | General Tab in XI, reset the "Set Default PDF Handler" to Adobe Reader XI and I can embed and read Acrobat files.
This obviously is an Adobe issue, although I suspect they will point to this: