I just installed a fresh copy of eclipse on my new Ubuntu 10.04 desktop and configured it for android development. This is the first time I got a dialog box with this error.
“The project cannot be build until the build path errors are solved”
The fix is to go to the project’s properties (project→right click→properties) and then in the Java Build Path tab check Android 2.2 or whichever version you are using (that’ll most probably be unchecked). And ka-boom! you’ll now be able to fire up the emulator
