why can't I upgrade from Adobe Acrobat Pro DC to Acrobat Reader DC?

Hi Charlesm,

As per the description above, I can understand that you are facing an issue in installing the Adobe Reader, Is that correct?

Adobe Reader is a free desktop version, and you can install it from  Adobe - Adobe Acrobat Reader DC Distribution  Link: https://get.adobe.com/reader/enterprise/

You cannot upgrade from Acrobat Pro Dc to a free version of Reader, you can install it and use it on your machine.

Assuming you are using a Windows machine. If you are unable to install the Reader back, then use the Adobe Cleaner tool to uninstall Acrobat Download Adobe Reader and Acrobat Cleaner Tool - Adobe Labs Link: http://labs.adobe.com/downloads/acrobatcleaner.html

Restart your computer and then install the Reader back.

Hope this helps, and keep us posted with the results.

Regards,

Anand Sri.