New KB
Alerts may not get forwarded as expected via a connector in Operations Manager
When using connectors to forward alerts in System Center Operations Manager 2007 (OpsMgr 2007) or System Center 2012 Operations Manager (OpsMgr 2012, SP1 and OpsMgr 2012 R2), in certain situations such as an alert storm (defined as a large number of alerts being generated in a very short period of time) there may be alerts that are not forwarded via a connector. When this occurs, these alerts will never be forwarded and will remain in a “New” state.
Cause and potential fix can be found in the KB article here:
http://support2.microsoft.com/kb/2277825/en-us
Good luck :p
