Creative Cloud stops working when I run Photoshop cs5

Hi Folks;

When I run Photoshop CS5 it makes changes to my system that stop Creative Cloud and Acrobat DC from working. I believe it's caused by CS5 making changes to the registry that are incompatible with Acrobat DC. How do I stop this happening, and/or how do I fix it without having to reinstall Cloud and DC each time?

Thanks, 

David