My JPortable Launcher stopped working recently (probably after a Java update) with “jPortable Launcher cannot be started. You may wish to re-install to fix this issue. (ERROR: jPortable [http://PortableApps.com/jPortable] could not be found)”. I reinstalled both JPortable Launcher and JPortable, but the error did not go away. After looking around a bit, it seems it looks for the JPortable launcher in
...\CommonFiles\Java\bin, while the installer installs the Java binaries into
...\CommonFiles\Java\jre1.8.0_152\bin. As soon as I moved the
bin directory one level up, it started to work again, so maybe a bug in the packaging/installer?