Problem: After the February 2026 cumulative update, many users found they could boot into normal mode but couldn’t access
C: drive. In
Properties → Security, the owner showed as
“Unable to display current owner” and permissions listed
“Unknown user”. Even administrators couldn’t add permissions back. Reset this PC often failed with
“No changes were made.”
Step‑by‑Step Fix (with screenshots)
1. Security tab shows no read permissions
(Your screenshot: “You must have Read permissions to view the properties of this object.”)
2. Advanced Security Settings shows broken ownership
(Your screenshot: “Owner: Unable to display current owner.”)
3. Add your user account back
(Your screenshot: Security tab with sundar
account Full Control checked.)
4. Change Owner to Administrators
(Your screenshot: Advanced Security Settings showing “Owner: Administrators (Sundarrajamani\Administrators)”).
