From your question, i assumed that, you are trying load a native library
There are two ways you can load the native library
System.loadLibrary(String) uses the default path.
System.load(String) uses the absolute path
Assume, you are working on the windows environment
The JVM will search for your dll file in java.library.path system property
If your dll directory is not specified in the java.library.path system property, you get this error.