An unusual bug has emerged, affecting Windows 11 users on Samsung devices, specifically preventing access to the main C: drive. This issue has surfaced following a recent system update, prompting a preliminary investigation by both Microsoft and Samsung. Their findings suggest that the root cause lies within a Samsung-specific application, rather than the Windows 11 update itself.
Details of the Issue
Users began encountering the message “C: is not accessible – Access denied” when attempting to launch applications or access files after installing the February 2026 security updates (KB5077181) on select Samsung devices. This includes various models of the Galaxy Book 4 laptops and certain Samsung Desktop models, as outlined in a notice from Microsoft.
Reports circulating on Reddit indicate that the problem may stem from broken Access Control Lists in Samsung’s factory image for Windows. This issue appears to be triggered when the Samsung Galaxy Connect and Galaxy Share Folder applications are updated. While some users in the r/sysadmin subreddit have proposed potential workarounds, these solutions have not been officially tested or verified by Microsoft. They involve making extensive changes to drive permissions, including altering the ownership of the entire drive, which is not advisable for long-term use.
Recommended Actions for Affected Users
If you own one of the impacted devices, such as the NP750XGJ, NP750XGL, NP754XGJ, NP754XFG, NP754XGK, DM500SGA, DM500TDA, DM500TGA, or DM501SGA, it is advisable to either remove the affected application from your device or revert to the currently recommended version at your earliest convenience. For those experiencing a loss of access to their files, patience is essential as users await an official resolution from Microsoft and Samsung.
