Unable to reference external library

Hello

I have an issue when I try to build my Qt app (within Qt creator, MVSC2013 compiler). I need to include the Bloomberg C++ API and I think this is what is the caused of my issue.
I have used the Qt tool to add the external library, and the following script has been generated in the .pro file:

win32:CONFIG(release, debug|release): LIBS += -L$$PWD/API/APIv3/C++API/v3.8.18.1/lib/ -lblpapi3_64
else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/API/APIv3/C++API/v3.8.18.1/lib/ -lblpapi3_64d
else:unix: LIBS += -L$$PWD/API/APIv3/C++API/v3.8.18.1/lib/ -lblpapi3_64

INCLUDEPATH += $$PWD/API/APIv3/C++API/v3.8.18.1/include
DEPENDPATH += $$PWD/API/APIv3/C++API/v3.8.18.1/include

But I have the following message in the "Issues tab" when I try to build the project (after running qmake):
LNK1104: cannot open file 'blpapi3_64d.lib'

Can you help me please?