Event ID 3006 Source EvntAgnt: Error reading log event record. Handle specified is 557040. Return code from ReadEventLog is 87.

In my case, I configured the events logs to "Overwrite events older than : .. " instead of  "Overwrite events as needed" and the problem was fixed

http://www.eventid.net/display.asp?eventid=3006&eventno=1219&source=EvntAgnt&phase=1