Can you elaborate on the issue? Those versions are compatible, both can open QVW generated by either. May it be that the file is corrupt?
What it's not compatible is trying to open a QVW file in Qlik Sense or a QVF file in QlikView. If that is the case you need the right software: QlikView Desktop for QVW and Qlik Sense Desktop for QVF. Or their corresponding server versions.