.etl extension

• To open *.etl file, open Event Viewer, right-click Saved Logs,  click Open Saved Log, and then locate to the *.etl file. Another way is using command “tracerpt

https://social.technet.microsoft.com/Forums/windows/en-US/bbd398bd-aab4-4719-bc2a-9aa05c0057f3/how-do-i-read-the-windows-7-backup-log-file-etl?forum=w7itprogeneral