Scala project won't compile in Eclipse; “Could not find the main class.”

Question

I have installed Eclipse 3.5.2 and today\'s Scala plugin from /update-current (that\'s Scala 2.8 final.) I can compile and run Scala projects consisting of a single singleto

Answer 1

I had the same error message with a Java application made by myself.

The problem was that I deleted (though inside Eclipse) a jar that belonged to the Java build path, without deleting it from the Java build path (project's Properties window). When I did it the class could compile and run again.