www.fastpictureviewer.com/forum

I am sorry to tell but the Codecs are not compatible with Windows 10. After an installation of a new build the thumbnail library is corrupted. I had to uninstall the codecs, clean the thumbnail library and reinstall the software to get it working

You just said it worked! Besides that, "installing a new build" imply toying with pre-release software, please don't blame my product for pre-release OS glitches... BTW both products are developed under Windows 10... I believe Id be the first to know