struts2-jquery-plugin-3.3.3.jar cannot be read or is not a valid ZIP file
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I'm using **Eclipse** to develop a **struts2** application using JQuery plugin. Unfortunately, i've tried many **jquery plugin versions**, but i get in the markers the following **errors** :


    Java Build Path Problems(1 item)
    Description	Resource	Path	Location	Type
    Archive for required library: 'A:/Struts2/HelloWorld/WebContent/WEB-INF/lib/struts2-jquery-plugin-3.3.3.jar' in project 'HelloWorld' cannot be read or is not a valid ZIP file	HelloWorld		Build path	Build Path Problem
    
    Java Problems
    Description	Resource	Path	Location	Type
    The project cannot be built until build path errors are resolved	HelloWorld		Unknown	Java Problem

I am obliged to use **Java 1.5**, could it be the cause? Thank you a lot in advance.