cannot be read or is not a valid ZIP file

1. Archive for required library: ‘WebContent/WEB-INF/lib/readme.txt’ in project ‘xxxxxxxxx’ cannot be read or is not a valid ZIP file

    用记事本打开项目根目录的.classpath文件，找到“<classpathentry kind=”lib” path=”WebContent/WEB-INF/lib/readme.txt”/>”这一行，删掉

2. The project cannot be built until build path errors are resolved

    第一个问题解决后，此问题也会消失

3. Target runtime Apache Tomcat v6.0 is not defined.

    打开项目根目录下.settings文件夹中的org.eclipse.wst.common.project.facet.core.xml文件，将“<runtime name=”Apache Tomcat v6.0″/>”这一句改成    现在所需要的tomcat版本，或者删除中间几行，只留下下面三行就行 “<?xml version=”1.0″ encoding=”UTF-8″?> <faceted-project> </faceted-        project>”