If you don't want it and it is a legit one, you can follow the guide here to uninstall it: http://blog.teesupport.com/atieclxx-exe-what-is-atieclxx-exe-and-how-to-shutdown-atieclxx-exe-in-windows-7/
You can try the step by step guide here to fix the problems:
http://blog.teesupport.com/fix-microsoft-word-error-a-problem-caused-the-program-to-stop-working-correctly-please-close-the-program/