Re: C&C 3 and Red Alert 3 won't launch.

I feel your pain. Many solutions presented here actually did not work for me as well. It's kinda random and sometimes it just starts working after Origin update. So you can try to uninstall the game and install it again when Origin update. If you have two drives, you can try installing it on the other one, see if that helps. There is also a recommendation to add the exe files and the launcher to the Windows firewall, try that too. Try also suggestions here (espescially the last page):

https://answers.ea.com/t5/C-C-The-Ultimate-Collection/Red-Alert-3-Will-not-launch/td-p/992422/page/2