I was working in a SQL Server 2005 setup case which failed while starting SQL Service with error:
SQL Server Setup could not connect to the database service for server configuration. The error was: [Microsoft][SQL Native Client][SQL Server]Login failed for user 'sa'. Refer to server error logs and setup logs for more information.
Then I reviewed the SQL Server error log and noted that
DateTime Logon Error: 18456, Severity: 14, State: 10
DateTime Logon Login failed for user 'sa'.
As per http://support.microsoft.com/kb/925744 State 10 corresponds to PASSWORD POLICY CHECK failure. The box I was working was in a workgroup. So we went ahead and used trace flag 4606 to byepass password policy check.
How to do that?
Create a reg key by name “SQLArg3” of type REG_SZ in the registry location
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\<Instance ID Created by the install>\MSSQLServer\Parameters
and add the value “-T4606”
Note: SQLArg3 should be replaced with a value higher than existing keys. So if you already have SQLArg0, SQLArg1, SQLArg2, SQLArg3 then add the value above with SQLArg4
Now stop SQL Server Service and click “Retry” in the setup window and setup should proceed further and complete successfully.
Use of trace flag 4606 is documented in http://support.microsoft.com/kb/936892