Operations Manager failed to correlate data. The rule or monitor trying to do the correlation was unloaded by the agent.
A rule or monitor that tried to correlate data failed. This is usually due to a misconfigured rule or monitor.
More details of what caused this issue can be found by examining the associated alert context. Look for the name of the rule or monitor (workflow name) and ensure that the rule or monitor is properly configured.
The following link will display all events indicating a possible problem with correlation:
View Correlation Events