Windows 10 Offline Language Packages Installer V1.5 -v1903 __exclusive__ -

A: LTSC 2019 is based on v1809, not v1903. Use the dedicated v1.2 LTSC version instead.

Right-click LangInstaller_v1.5 -v1903.exe and select Run as Administrator . Windows 10 Offline Language Packages Installer v1.5 -v1903