Why can't I save file in Eclipse Juno?

eclipse, eclipse-juno

Solution

This is a known issue in Eclipse Juno:

https://bugs.eclipse.org/bugs/show_bug.cgi?id=396418

As a workaround, use 'Save All': Shft+Ctrl+S

Problem

Sometimes I cannot save a file in Eclipse Juno. The File->Save option is greyed out and Ctrl+S does not work. What's going on?

Original source