Server Side Software Update Logs:
SUPsetup.log – Installation of SUP Site Role.
WCM.log, WSUSCtrl.log – Configuration of WSUS Server/SUP.
WSyncMgr.log – SMS/WSUS Updates Synchronization Issues.
Objreplmgr.log – Policy Issues for Update Assignments/CI Version Info policies.
RuleEngine.log – Auto Deployment Rules.
Client Side Software Update Logs:
UpdatesDeployment.log – Deployments, SDK, UX.
UpdatesHandler.log – Updates, Download.
ScanAgent.log – Online/Offline scans, WSUS location requests.
WUAHandler.log – Update status (missing/installed – verbose logging), WU interaction.
UpdatesStore.log – Update status (missing/installed).
%windir%\WindowsUpdate.log – Scanning/Installation of updates.