One of the administrative tools in Microsoft Management Console, Event Viewer maintains logs about program, security, and system events on your computer. You can use Event Viewer to view and manage the event logs, gather information about hardware and software problems, and monitor Windows security events.
If Event Viewer reports on startup that one or more of your log files is corrupt, you can remedy the situation as follows:
Open the Event Viewer.
Rightclick on the corrupt log in the left pane and click Properties.
Click the Clear button in the Properties dialog box.
You cannot delete or rename the log files while the Event Log service is running.