Netbeans can't find external jar

I'm fairly new to Java and开发者_如何转开发 need to add an external Jar to the project in netbeans. I've created a library with that Jar using Tools --> Libraries, and added the library in the project Properties --> Libraries under compile, but it still returns "Package does not exist".

Any help?

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What version of Netbeans are you using? Make sure your libraries are located outside of the project directory. Just making sure when you add the jar, you don't just add the folder containing them but the actual jar -right?
Try building the project to see if that helps.

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Perhaps the library was created incorrectly. If the package structure in the JAR isn't correct, the class loader won't be able to find the .class file.

Open the JAR with WinZip and confirm the contents.