Solution by Event Log Doctor

This event is logged by the "SNMP Service", a component of Windows.

The SNMP Service is monitoring the event logs and will log this error when it is unable to read a particular (large) event in a log, apparently due to a internal buffer size of the SNMP Service that is too small.

Some event log entries, for example "Application Error" events in the Application log, may include hundreds of kilobytes of binary data which confuse some services, including the SNMP Service and SQL Server Agent service.

In most cases this entry can be ignored.