Before diving into settings, perform a full restart. Not a "Shutdown" (which often uses Fast Startup and saves the kernel state), but a . This forces Windows to kill all active tracing sessions and start fresh. 2. Flush the ETW Logs
Delete the contents of the RtBackup folder and restart your PC. Windows will recreate these files cleanly upon reboot. 3. Restart the Windows Update Services Sometimes the service responsible for the trace is hung. Before diving into settings, perform a full restart
Under the tab, ensure "Enabled" is checked, but if the error persists, try toggling the "Circular" log mode to help overwrite old data. ensure "Enabled" is checked
In plain English: Windows is trying to start a tracing session (a log that tracks what Windows Update is doing), but it’s hitting a snag because a session with that same name or ID is already running or wasn't shut down properly. It’s like trying to save a file in a folder where a file with that exact name is already open. Is This Critical? but if the error persists
Search for in the Start menu and open it. Expand Data Collector Sets on the left. Click on Startup Event Trace Sessions . Locate WindowsUpdateTracelog in the list. Right-click it and select Properties .
The 0xc0000035 error is rarely a "system killer." It’s a minor conflict in how Windows tracks its own update progress. By clearing the folder or restarting the update services, you usually tell Windows to stop overthinking and start the log fresh.
You may need to take ownership of this folder to delete files inside it.