Fix Previous Foxit PDF Editor Installation Detected
Get-A-Previous-Installation-of-the-Foxit-PDF-Editor-Detected-when-running-the-Foxit-Editor-Installer
Answer
If an old version exists, running the new installer (MSI, EXE) of the newer version of Foxit PDF Editor/Reader can upgrade it.
But it does not always work. It only works if the new installer's type (MSI, EXE, Multi-language pack, or English pack) matches the installer used to install the existing Foxit Editor/Reader.
For example, if the current Foxit Editor/Reader is installed via the EXE English installer, the new installer for a new version should also be EXE English.
Otherwise, you will have to uninstall the current version and then install the new version.