Dx bad class file magic (cafebabe) or version (0033.0000) with ADK14

Question

Since moving to ADK14, I have been unable to build new apks for release on my Windows 7 system.

Building fails with \"conversion to dalvik format failed with error 1

Answer 1

This error occurs when you use a .jar file that is not using any feature of Java 6 or higher but was built using Java 6 or higher, according to informIT.com. Apparently, Google doesn't include JDK 7 in Android's system requirements.

So the solution, that worked for me is very simple. Build the .jar file using Java 5 or less.