Hi, I had the same error message for months, and found this post via google.
See also: https://community.amd.com/thread/222989
So here is what helped me:
In Dec 2017 I updated my Windows 10 to the Fall Creators Update and the latest AMD drivers for my R9 380.
After that I always got the same error message after each PC reboot: "RadeonSettings.exe - Application Error. The application was unable to start correctly (0xc0000142)."
It did not seem to have any negative effects (my Radeon Settings worked just fine), but I could not get rid of this error message even with a DDU driver uninstall and then installing all the latest AMD drivers (17.12, 18.1, 18.2.1, 18.2.2 ...) again and again.
Today I stumbled over a reddit post with the solution for my problem: I had to disable the "use my sign-in info" option (Windows Settings > Accounts > Sign-in Options > "Use my sign-in info to automatically finish setting up my device..."), which was apparently introduced in the Win 10 Fall Creators Update. After disabling that option, the strange error message after reboots finally disappeared for me.