Adobe Acrobat Upgrade

I was trying to upgrade my Adobe Acrobat from 2.0.0.0  to 2.3.0.0 since it was a mandatory update and I got an error everytime.  I saw on one of your sessions to uninstall the Acrobat and then to download the next version.  I did the uninstall but where do I get the upgrade without cost, I need help.  I guess I will need to download a complete version of the program.