MSSQLSERVER_9790
Details
Product Name  | 
SQL Server  | 
Product Version  | 
10.0  | 
Product Build Number  | 
10.00.0000.00  | 
Event ID  | 
9790  | 
Event Source  | 
MSSQLSERVER  | 
Component  | 
SQLEngine  | 
Symbolic Name  | 
SB3_XMIT_ERROR_ENTRANCE_BROKER_SINGLE_USER  | 
Message Text  | 
Unable to route the incoming message. The system database MSDB containing routing information is in SINGLE USER mode.  | 
Explanation
An error occurred while trying to classify a message received off the wire because the MSDB database was in Single User mode.
User Action
Change MSDB to be in MULTI USER mode with the ALTER DATABASE command.