I have same issue - I have Vista...I downloaded Adobe Reader 9, installed fine and still get the msg when I click on the link: "The Adobe Acrobat/Reader that is currently running can not be used to view PDF files in a web browser. Adobe Acrobat/Reader version 8 or 9 required. Please try again."
But only if it's sent as an attachment, I don't have a problem opening file.
Any suggestions, help? Greatly appreciate it!