If you have Java phone, I believe that you have know JAD file. File Extension JAD (Java Aplication Descriptor) is the kind of file contains a set of attributes enabling the identification, retrieval, and installation of MIDlets. MIDlets, include both .JAD and .JAR (Java Archive) files, is a type of Java program developed for the Java ME virtual machine; commonly used to package Java games and applications developed for cell phones.
Most problem with file extension JAD and many other file format are registry conflict. If you face such problem, try to scan and fix your registry. If you don't know how, you should visit website that provide comprehenship information about file extension JAD and how to fix the problem. FileExtensionJad.com provide More Info Regarding File Extension Jad