If you are a Samsung Galaxy Book owner experiencing sudden severe issues, you are not alone. A recent Windows 11 update by Microsoft seems to have caused significant problems for these popular PCs, leading to users losing access to the crucial C drive, with a message displaying “C:is not accessible – Access denied.”
This access blockage is preventing affected users from opening files or running certain applications like Microsoft Outlook, Office apps, and specific web browsers. Some of the model numbers believed to be impacted include NP750XGJ, NP750XGL, NP754XGJ, NP754XFG, NP754XGK, DM500SGA, DM500TDA, DM500TGA, and DM501SGA.
Microsoft has acknowledged the issue, stating that some Samsung device models are experiencing C drive access loss after installing the February 2026 security update (KB5077181) and subsequent updates. Users may encounter the error message “C: is not accessible – Access denied,” which hinders file access and impedes the launch of applications such as Outlook, Office apps, web browsers, system utilities, and Quick Assist.
The problem is suspected to stem from Samsung’s Galaxy Connect app, which offers features like screen mirroring, file sharing, and data transfer between Galaxy smartphones and Windows PCs. The app has been temporarily removed from the Windows app store while a solution is being developed.
Microsoft mentioned, “The affected Samsung Galaxy Connect application was temporarily removed from the Microsoft Store to prevent further installations. Samsung has republished a stable previous version of the application to prevent additional device issues. Recovery options for impacted devices are limited, and Samsung is working with Microsoft to explore remediation strategies.”
The timeline for a fix release remains uncertain. If you own a Samsung PC and have not updated to Windows 11 versions 24H2 and 25H2, it is advisable to hold off. Users on Windows 11 versions 24H2 and 25H2 are recommended to refrain from updating further.