ILOG CPLEX 11.0 Getting Started > Tutorials > Concert Technology Tutorial for Java Users > Compiling ILOG CPLEX in ILOG Concert Technology Java Applications > In Case Problems Arise

If a problem occurs in the compilation phase, make sure your java compiler is correctly set up and that your classpath includes the cplex.jar file.

If compilation is successful and the problem occurs when executing your application, there are three likely causes:

  1. If you get a message like java.lang.NoClassDefFoundError your classpath is not correctly set up. Make sure you use -classpath <path_to_cplex.jar> in your java command.
  2. If you get a message like java.lang.UnsatisfiedLinkError, you need to set up the path correctly so that the JVM can locate the ILOG CPLEX shared library. Make sure you use the following option in your java command:
  3. -Djava.library.path=<path_to_shared_library>
  4. If you get a message like ilm: CPLEX: no license found for this product or ilm: CPLEX: invalid encrypted key "MNJVUXTDJV82" in "/usr/ilog/ilm/ access.ilm" run ilmcheck, then there is a problem with your license to use ILOG CPLEX. Review the ILOG License Manager User's Guide and Reference to see whether you can correct the problem. If you have verified your system and license setup but continue to experience problems, contact ILOG customer support and report the error messages.