I imported a Java Web application from Sourceforge, and I did three working weeks efforts to get rid off all red crosses attached to the project name and packages, but now I cou
Please look at this answer. If clean won't help, then probably something is wrong with your project's specific settings. I would suggest you to examine every file inside .settings/ directory.
I know this is not a ready-to-go solution, but may be at least a starting point.