Problem after rename of the directory name

[ZACXON]

I made a copy to upgrade one application (done with Qt 4.7.4 (32 bit) + mingw )
from
C:_IHM_V5.0\source
to
C:_IHM_V6.0\source

I changed the project configuration (that's mean updating the application.pro.user file ) for the new direction to the new source directory .
After compilation the application begin but seems to not be able to use functionnality done by the include files.
the include files are found when compiled in the sub directory ( include files in C++ to drive an IXXAT apparatus )
C:_IHM_V6.0\source\inc
I don(t understant what's going wrong, V6.0 have exactly the same files than V5.0 ( Winmerge said it to me )
the application works well on C:_IHM_V5.0\source\release or debug directory but not when launched from V6.0\ release, even if that one finished with error code 0.

.pro file is modified too for include path only

TEMPLATE = app
TARGET =
DEPENDPATH += .
INCLUDEPATH += C:/_IHM_V6.0/source/inc.
DEPENDPATH+=C:/WINDOWS/system32

SOURCES +=
main.cpp
vcilibloader.cpp
VciDevice.cpp
DeviceList.cpp
ReadMsg.cpp
PageParam.cpp
RetourAxe.cpp
MaFenetre.cpp
ConfigAxe.cpp
Trajectoire.cpp
Comboboxdelegate.cpp
Onglet_Axe.cpp
Onglet_Config.cpp
Delay_It.cpp

HEADERS +=
inc/stdtype.h
inc/vciIdType.h
inc/vci3.h
inc/vcitype.h
inc/baltype.h
inc/cantype.h
inc/vcictrltype.h
inc/vcinpl.h
inc/vcierr.h
inc/predef.h
vcilibloader.h
VciDevice.h
DeviceList.h
ReadMsg.h
PageParam.h
RetourAxe.h
MaFenetre.h
ConfigAxe.h
Trajectoire.h
Comboboxdelegate.h
Onglet_Axe.h
Onglet_Config.h
Delay_It.h

FORMS +=

TRANSLATIONS +=
ISPMotorInterface_en.ts

OTHER_FILES +=

RESOURCES +=
myapp.qrc

If somebody can help me to undestand what's going wrong or what I forget to change .

Thanks

[sierdzio]

If there is any existing Makefile in your new directory, please remove it. Also, you can remove .pro.user file completely and let Qt Creator generate a new one for you automatically.

[ZACXON]

Thank you,
compiling and running the Qt application works well, even if I remove the makefiles and pro.user file before, it is the same

I think the dynamic linking of the Ixxat's DLL don't works, but I do not understand why , because the environments are similar

or perhaps there is another problem due to a message I can read (on relase only) V5.0 before running the message window says :

FTH: (5292): *** Fault tolerant heap shim applied to current process. This is usually due to previous crashes. ***

even with this warning, the application run , the dll can be used , and the Qt application quit with code 0