Since Qt 5.4.0, creating a new .ini file with the help of QSettings causes the file to have very limited rights (file permissions 600 on Unix). This is a regression from Qt 5.3 and earlier, where the same file was created with normal rights (644 typically).
QSettings s("settings.ini", QSettings::IniFormat);
qDebug() << "Can everyone read file?" << file.permissions().testFlag(QFile::ReadOther);