An important piece of information that you need to be aware of before installing CC 2015 digital video applications is that the installation of a CC 2015 application uninstalls the same CC 2014 application by default.
To install the latest version without uninstalling the previous version:
- Within the Update Dialog Box, click the arrow to the right of Advanced Options to expose those settings
- Uncheck “Remove old versions”
- Click “Update”
More details about this can be found in this blog: Creative Cloud Delivering More Choice for Installations. You can also read about this issue and other reasons why you might want to retain previous digital video application in this post on After Effects team blog.
If you have mistakenly uninstalled Premiere Pro CC 2014, and are still using it for some of your projects, you will need to reinstall the application.