You may want to DL the latest version.Or, use Add/Remove first then reboot then install the latest version and select the custom install something similar to this;
Click here to download the current version of PAF (version 18.104.22.168). (To check your current PAF version, launch PAF, click Help, and then then choose About Personal Ancestral File.) PAF 5.2 will allow you to convert Personal Ancestral File 3.0 and 4.0 data files to its improved file format. You can still keep a copy of your original files in Personal Ancestral File 3.0 or 4.0.
Best regards with your searching: Sir Gary in New Orleans