Hello, I'm working in Qt Creator/Win7, and have been trying to understand how to use external libraries for 2 hours already.

I've read the qmake documentation and looked for info on google but I didn't find any satisfactory examples.

I've added qextserialportd.dll and qwt5.dll files to my main directory where all the project files are.

here is my .pro file:
Qt Code: 
  1. QT       += core gui
  2.  
  3. TARGET = myser2
  4. TEMPLATE = app
  5.  
  6.  
  7. SOURCES += main.cpp\
  8.         myser2.cpp
  9.  
  10. HEADERS  += myser2.h
  11.  
  12. FORMS    += myser2.ui
  13.  
  14. LIBS += -lqextserialportd
  15. LIBS += -lqwt5
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in myser2.h, I've put
Qt Code: 
  1. #include <qextserialport.h>
  2. #include <qwt_plot.h>
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now, when I try to build, it can't find any of those files.
I've tried all sorts of different notations for LIBS:
Qt Code: 
  1. LIBS += <path>/qwt5.lib
  2. LIBS += <path>/qwt5.dll
  3. LIBS += qwt5.lib
  4. LIBS += -L<path> -lqwt5
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but nothing works

If you could explain me what I am forgetting, that would be great. An example project would be even better.
Thanks