DRM video broken, SMBv1 file sharing dead

September’s update broke DRM video playback — Blu-ray apps, DVD players, and digital TV applications all failed with copyright protection errors or black screens. The Enhanced Video Renderer couldn’t handle HDCP enforcement anymore. Meanwhile, SMBv1 file sharing stopped working entirely with repeated “System error 86” credential prompts, even with correct passwords. Legacy NAS devices and printers became inaccessible. Some machines had their network profiles silently reset to “Public,” disabling file and printer sharing. Microsoft managed to break both watching movies and accessing network files in a single update.