Currently, Windows Vista event logs can be cleaned by running an advanced command prompt, or disabling User Account Control, and typing...
wevtutil el > EventLogs.txt
...to list all available event logs to a file called EventLogs.txt, followed by...
wevtutil cl > logname
...where "logname" is one of the logs listed in the EventLogs.txt file that requires clearing.
Annoyingly, if User Account Control is enabled the event logs cannot be cleared with a batch file, even when set to "Run As Adminstrator" from its properties, and access is denied.
The majority of Windows Vista's event logs are stored in "%windir%\System32\WinEvt\Logs" and are locked against deletion. Whereas they have a size limit, which is configurable from the Event Viewer, they can take up a lot of hard disk space due to the sheer number of logs. Clearing the log files shrinks them back down to their standard 68KB size.
It would be nice if the above functionality could be included in CCleaner as standard. The program may need elevated privileges to overcome the User Account Control issue, but the feature would certainly be a welcome one considering the overall amount of hard disk space gained.
Regards
DJ