Hi...
When you install any software (not just Reallusion software) you will often find additional shared 3rd party applications and utilities will be installed as well as the main program files. An example of this are the Microsoft Visual C++ redistributables which are very commonly installed by a lot of software. However, when uninstalling only the program files will be uninstalled because things like the Microsoft Visual C++ redistributables may be required by other installed software and uninstalling will stop the other software from running.
In the case of the PostgreSQL content that is in the Reallusion Common folder, you can simply delete the folder if you no longer plan to use any Reallusion software. If you have any other Reallusion software installed then this folder should be left as it may still be needed.
C:\Program Files\Common Files\Reallusion\PostgreSQL\bin
Peter
Forum Administrator
www.reallusion.com