OK, I can't say what is wrong, but having spaces in include/lib paths isn't good (although it should work with quotes). Try to move include dir to somewhere like c:\opencv, then change .pro file:
Qt Code: 
  1. INCLUDEPATH += c:/opencv/include
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and in your sources use:
Qt Code: 
  1. #include <opencv/cv.h>
  2. #include <opencv/cvaux.h>
  3. #include <opencv/highgui.h>
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It should find headers fine. At least it works for me in such way in my projects.