#include <QString> error

[momesana]

Do you include userFunc.h from another project's directory (i.e. something outside of your projects root directory) or does it belong to your current project?
If it is from an outside project you set INCLUDEPATH in your projects .pro file to point to the directory containing the mentioned header and use unqualifiled header includes.

INCLUDEPATH += . /path/to/userFunc/

INCLUDEPATH += . /path/to/userFunc/

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#include <userFunc.h>
instead of
#include <../../userFunc.h>

#include <userFunc.h>
instead of
#include <../../userFunc.h>

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