How to update Adobe Acrobat 9.X?

I'm trying to update Adobe Acrobat 9.0 to the latest revision Adobe Acrobat 9.5.5. I downloaded each of the updates, but I keep getting a reminder that normal windows update does not apply. I downloaded the files and normally would then click on each update to update the preceding revision in order. However, it appears this is not the way for these revisions. How do I update the Adobe Acrobat 9.0?