System.Data.SqlClient.SqlException when try to run script SQL from C# code

Question

I've installed SQL Server 2012 Express. I'm doing some test with this and Server 2008 Express.

With 2008, all is ok. But with the 2012, I get some troubles.

I'm using it from my c# app, with code like this:

t = server.ConnectionContext.ExecuteNonQuery("SELECT * FROM sys.server_principals");

The query in the row above is only a test I've done, after the script I need get error.

But, also this get the same error: MODIFY FILE failed. Specified size is less than or equal to current size. But why? I saw around that this error comes when something is done about the log... or not?

Why I get this error? The login data are correctly. This a new installation, so I am logged in as sa (the script will then create a new user).

The same script works perfectly with SQL Server 2008 Express. I don't get why with 2012 is in this way.. what am I missing? Further, I install both 2008 and 2012 from command line with the same parameter:

/q /hideconsole /action=Install /features=SQL /instancename=SQLEXPRESS 
/securitymode=SQL /sapwd=xxx /enableranu=1 /sqlsvcaccount="NT Authority\Network Service" 
/AddCurrentUserAsSqlAdmin /IAcceptSqlServerLicenseTerms  
/skiprules=RebootRequiredCheck

Anyway, the script I want to run is (but, as I said, also the simply SQL above causes the error):

IF NOT EXISTS (SELECT * FROM sys.server_principals WHERE name = ****')
    CREATE LOGIN [icaddb] 
       WITH PASSWORD = '****', DEFAULT_DATABASE = [master],   
       DEFAULT_LANGUAGE = [us_english], CHECK_EXPIRATION = OFF, CHECK_POLICY = ON
GO

EXEC sys.sp_addsrvrolemember @loginame = ****', @rolename = N'sysadmin'
GO

EDIT:

Answer 1

The problem was this:

CREATE DATABASE [IN4MATICSystemSCRIPT_TEST2] 
GO
ALTER DATABASE IN4MATICSystemSCRIPT_TEST2 MODIFY FILE 
( NAME = N'IN4MATICSystemSCRIPT_TEST2' , SIZE = 8384KB , MAXSIZE =     UNLIMITED, FILEGROWTH = 1024KB )
GO
ALTER DATABASE IN4MATICSystemSCRIPT_TEST2 MODIFY FILE 
( NAME = N'IN4MATICSystemSCRIPT_TEST2_log' , SIZE = 24384KB , MAXSIZE =     2048GB , FILEGROWTH = 10%)
GO

Solved removing these rows.