Users of Samsung Galaxy Book laptops are facing significant issues following a recent Windows 11 update. Many individuals have encountered a message stating “C:is not accessible – Access denied,” leading to the inability to open files or use certain applications like Microsoft Outlook and Office apps. The problem seems to affect specific model numbers, including NP750XGJ, NP750XGL, NP754XGJ, and more.
Microsoft has acknowledged the issue, attributing it to the February 2026 security update (KB5077181) and subsequent updates. The error message “C: is not accessible – Access denied” hinders access to files and the launch of various applications. The problem occurs during routine actions like accessing files or launching applications without requiring specific user actions.
The root cause of the issue is believed to be Samsung’s Galaxy Connect app, which offers features like screen mirroring and file sharing between Galaxy smartphones and Windows PCs. The app has been temporarily removed from the Windows app store while a solution is being developed.
Although the timeline for a fix is uncertain, Samsung Galaxy Book owners are advised to hold off on updating to Windows 11 versions 24H2 and 25H2. Those already on these versions are recommended to refrain from making any changes until further updates are released.