The program adds itself to the registry key "OpenWithList" (under HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\ Explorer\FileExts\.extension\OpenWithList ) for every image format opened.
For more detailed informations regarding the meaning of this registry key please read in the Microsoft article How to Remove Programs from the "Open With" List. Therefore the recommendation in the documentation under
Keys and values to ignore regarding the key "Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts" is definitely wrong and should be removed.
For the case that someone already use PhotoFiltre Portable it is necessary, that you manually remove the appropriate entries from the registry key OpenWithList (right click on the entry and select "Delete" from the context menu). You can find an illustrated instruction in the german Microsoft article under the section Einen Eintrag löschen.
Here now the necessary code, which must added in the section [RegistryKeys] into the file PhotoFiltrePortable.ini:
Finally, the download link for the revised version: PhotoFiltrePortable_7.1.0_Rev1.paf.exe
Download Size: 5,60 MB