title: Java - Could not find the main class?
body: <p>I'm having a hard-time with a Java error. I'm getting this when double-clicking on my compiled project Jar file in order to run it:</p>
  
  <pre><code>Could not find the main class: testPackage.testFrame. Program will exit.
  </code></pre>
  
  <p>However, my main class is cleary defined in the project properties. Furthermore, everything works fine when I run the project directly from NetBeans.</p>
  
  <p>I'm using the ip2c.jar third-party library to determine countries from IP addresses. If I comment the class that is using the ip2c.jar file, I don't get the error.</p>
  
  <p><strong>How can a third-party library be preventing the JVM from finding my main class?</strong></p>