Are you using Windows computer or Mac?
Quit Creative Cloud application.
Navigate to Applications > Utilities.
Locate Adobe Creative Cloud and Adobe Application Manager folder under Utilities window and trash both folders.
Click on the below link and download & run Adobe Cleaner tool :
Select the option "Adobe Application Manager for Mac OS X 10.6" and then click on "Clean up Selected" .
https://helpx.adobe.com/content/help/en/creative-suite/kb/cs5-cleaner-tool-installation-pr oblems/_jcr_content/main-pars/accordion_container_1/accordion-par/accordion-item-1/accord i on-item-par/procedure/proc_par/step_3/step_par/download/file.res/AdobeCreativeCloudCleane r Tool.zip
Click on the below link and download Adobe Application Manager and install the same .
Once the installation process is completed, installation box will disappear.
Then open " Applications" folder and locate Adobe Application Manager launch icon and double click on it and update.
Then try to install CC apps and check.
this looks to have worked!!! thank you so much!
You are most welcome .
Brucgovn: Want to tell you that your solution helped me out as well.
You are welcome .
Update : Adobe Cleaner tool new link :