Adobe Acrobat Reader DC

Installed the new version of Reader after deleting old version because of problems.  I am running Windows 7. When I try to access a PDF document from an internet site I get an Adobe Reader Protected Mode message. if open protected I get a blank screen. If I do the same with a PDF doc on my hard drive I can view it. If I open with unprotected I get an Adobe PDF Document error "There is a problem with Adobe Acrobat/Reader. If it is running, please exit and try again. (15:3)"

How can I get a clean install?