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My application works fine on the local development server, but when I upload it to google app engine it keeps getting an error and does not start at all.
If I use VaadinServlet instead on GAEVaadinServlet in web.xml; the application starts fine, but can't handle clicks or something else. There is always a "Communication Error".
Here are my files:
Here the error I receive:
This happens when I replace GAEVaadinServlet with VaadinServlet in web.xml (on every button click):
Please help, I don't know what to do any more ...