Eclipse: Project cannot reference itself

Question

I am not able to add Dynamic Web Module 3.0 facet due to this error. No idea what is wrong with my project settings.
This is a duplicate question but accepted answer provides a url as solution which no longer work.

Answer 1

Deleted .classpath and project settings files from project folder. Then imported the maven project again.
It works fine after that.

Answer 2

Please delete

< wb-resource deploy-path="/WEB-INF/classes" source-path="/"/ >

from org.eclipse.wst.common.component under .settings folder.