Thanks for all the help but I am still having issues and its driving me nuts....

as I understand it the libXXX.a file is the library containing all the classes and functions... I found http://doc.trolltech.com/4.5/qmake-v...ence.html#libs and its helped me out a bit but I still cant get it to work

In my .pro file of the GUI app I have LIBS += -L"C:/Documents and Settings/......../c++/disspertionLib/release" -ldisspertionLib

the folder release contains all the .o and libxxx.a files

but I am still getting errors:

mainwindow.cpp:7:24: coordinate.h: No such file or directory
mainwindow.cpp:8:25: boundaryMap.h: No such file or directory
mainwindow.cpp:9:22: particle.h: No such file or directory
mainwindow.cpp: In member function `void MainWindow:n_btnGo_clicked(bool)':
mainwindow.cpp:53: error: `boundaryMap' was not declared in this scope
mainwindow.cpp:53: error: expected `;' before "bound"
mainwindow.cpp:55: error: `Particle' was not declared in this scope

etc......


btw... how do I include the library in my code? At the moment I still have
#include "coordinate.h"
#include "boundaryMap.h"
#include "particle.h"

which were the origional names of the files before I put them into the library... do these still stay the same or do I need to change them?

Thanks again