SUMMARY The KStars Add-on Installer, which runs when clicking the "Download extra data" button in the startup wizard, has a number of issues that prevents catalogs from being installed. This has happened on two different VMs, with slightly different results. STEPS TO REPRODUCE 1. Launch a new KStars install, or launch the Startup Wizard 2. Click the Download Extra Data button 3. Attempt to install each data set. OBSERVED RESULT Some data sets cannot be installed because of a file-not-found error. Sometimes, exiting this window and clicking on the Download Extra Data button again sometimes seems to show that some of the failed catalogs installed (some, which were marked Install before, now are marked Uninstall). However, others are still marked Install, or marked Install Again. EXPECTED RESULT All catalogs should install without error, and behavior of the window should be consistent between executions. I believe this runs normally in UNIX and MacOS, so it may be a Windows-only issue. SOFTWARE/OS VERSIONS Windows: 10 macOS: Linux/KDE Plasma: (available in About System) KDE Plasma Version: KDE Frameworks Version: Qt Version: ADDITIONAL INFORMATION