Windows 11 Bug Locks Samsung Users Out of C Drive After Update

A critical bug in the February 2026 Windows 11 security update (KB5077181) has rendered the C: drive inaccessible for users on certain Samsung laptops, particularly the Galaxy Book 4 series. The issue, which affects Windows 11 versions 24H2 and 25H2, prevents users from launching applications and performing basic tasks, leading to significant disruptions. Reports indicate that the problem is predominantly observed in Brazil, Portugal, South Korea, and India. Microsoft is currently investigating the issue in collaboration with Samsung to determine whether it stems from the Windows update or Samsung's software. A temporary workaround involving changing the ownership of the C: drive has been suggested but is discouraged due to security risks. As of now, no official fix has been released, and users are advised to wait for Microsoft to address the issue.

Key Points: • A bug in Windows 11 blocks access to the C: drive for some Samsung laptop users. • The issue primarily affects Samsung Galaxy Book 4 devices in specific regions. • Microsoft is investigating the root cause and has not yet provided an official fix.