GWT/ Eclipse: ClassNotFoundException com/google/gwt/dev/Compiler

Question

i recently updated from GWT 2.0.4 to 2.1.0. Since then I cannot compile my GWT application anymore. When I click on the GWT compile button of the GWT eclipse plugin I get th

Answer 1

I had the same problem, some java program had been installed declaring a "ClassPath" environment variable, and invalidating the gwt plugin for ANY version of eclipse, from 3.6 (helios) to 4.2 (juno). Note that environment variables are case-insensitive in Windows OSs. Solution: eliminate the system/user variable declaration and declare the variable in a/the launch script for the concerned program.