Microsoft says the March 2026 cumulative for Windows 11 (KB5079473) is not responsible for the wave of dramatic failure reports — and an investigation into machines that can’t access their C: drive points to a faulty Samsung app, not the Patch Tuesday rollup. com]
Background / Overview
Microsoft...
A wave of Windows 11 systems — most noticeably certain Samsung Galaxy Book models — have been hit by a frightening post-update failure that can leave the PC’s system volume effectively locked and users locked out of their own files and applications. After Microsoft’s February 10, 2026 cumulative...
A cluster of Windows 11 systems worldwide began reporting a startling failure in March 2026: after installing Microsoft’s February cumulative update (KB5077181), some laptops — most prominently certain Samsung Galaxy Book models — started showing the error “C:\ is not accessible – Access...