This SBS 2008 has a high number of EventID 18456 from MSSQL$SQLSERVER (about 3 every minute)
Login failed for user 'NT AUTHORITY\SYSTEM'. Reason: Failed to open the explicitly specified database. [CLIENT: <local machine>]
What could be the root cause of these errors?
1. This server is SQL 2008 R2 & SQL Server 2005 (Express?)
2. SQLSERVER has a CRM database on it which is managed by a 3d party