I just installed xcode 3.1.4 on mac 10.5.6, and used External Build to compile an existing C++ project. The Build has some errors, showing up on the Build Results Window. However, the bottom part of the window shows a No Editor message; double clicking on most error messages does nothing. However, for a few errors, related to stl vector classes, some vector class files open up in the Editor Window, though the error is in the files in my project. I have set the editor in File Types to Emacs for all file types in Preferences. Why are my project files not opening, while some other files like vector.tcc, stl_vector.h are opening?