Nobody can tell you anything without proper system info or other technical details.
On a PC & having the exact same issue.
Please contact Adobe support. And, if they solve it for you, please let us know what the solution was!
In the meantime, if you just need to get to work quickly, try AE CC 2014: How to Find and Install Previous Version of Adobe Apps in CC 2015
I got the same message on Mac OS X Yosemite, contacted Adobe Support, and they told me you just have to update your system (I was on 10.10).
I did this and problem solved Ae opens up perfectly.