Introduction Windows Update is the lifeblood of system maintenance, security, and performance on Microsoft operating systems. However, few errors are as cryptic—and initially alarming—as the message: "Session WindowsUpdateTraceLog failed to start with the following error 0xc0000035."
Open an administrative Command Prompt and run logman query -ets . If you see a WindowsUpdateTraceLog session in a “Running” or stale state, stop it immediately. Then, smile — you’ve just fixed the problem. Introduction Windows Update is the lifeblood of system
net start wuauserv net start cryptSvc net start bits net start msiserver net start EventLog Then, smile — you’ve just fixed the problem
with the following commands (run as Administrator): net stop wuauserv net stop cryptSvc net stop
If you reach Method 8 and the error still persists, the underlying cause is likely a deeper OS corruption requiring a clean installation. However, for 95% of affected systems, Methods 1–3 will resolve the issue in under ten minutes.
net stop wuauserv net stop cryptSvc net stop bits net stop msiserver net stop EventLog ren C:\Windows\SoftwareDistribution SoftwareDistribution.old ren C:\Windows\System32\catroot2 Catroot2.old ren C:\Windows\Logs\WindowsUpdate WindowsUpdate.old
This error typically appears in the under Applications and Services Logs > Microsoft > Windows > WindowsUpdateClient > Operational . It does not always manifest as a pop-up dialog box, but it can be the hidden culprit behind update failures, high CPU usage from the TrustedInstaller service, or Windows Update getting "stuck" at 0% or 99%.