KB5077181 was released about a month ago as part of the February Patch Tuesday rollout. When the update first arrived, users reported a wide range of problems, including boot loops, login errors, and installation issues.
Microsoft has now acknowledged another problem linked to the same update. Some affected users see the message “C:\ is not accessible – Access denied” when trying to open the system drive.


No one smart is going into windows dev in 2026. It’s like working on IBM mainframes. Only people left to work are middle of the road new grads they hire and boomers who are retiring.