Error Installing SQL Server 2008 (July CTP)

When I install July CTP (do not have any other version of SQL on my laptop)

I am consistently getting an error

Error Code: 18456
MSI (s) (C0!4C) [01:01:33:703]: Product: Microsoft SQL Server 2008 -- Error 29515. SQL Server Setup could not connect to the database service for server configuration. The error was: [Microsoft][SQL Server Native Client 10.0][SQL Server]Login failed for user 'sa'. Refer to server error logs and setup logs for more information. For details on how to view setup logs, see "How to View Setup Log Files" in SQL Server Books Online.

Error 29515. SQL Server Setup could not connect to the database service for server configuration. The error was: [Microsoft][SQL Server Native Client 10.0][SQL Server]Login failed for user 'sa'. Refer to server error logs and setup logs for more information. For details on how to view setup logs, see "How to View Setup Log Files" in SQL Server Books Online.
<Func Name='GetCAContext'>
<EndFunc Name='GetCAContext' Return='T' GetLastError='203'>
Doing Action: Do_sqlScript
PerfTime Start: Do_sqlScript : Tue Aug 28 01:01:33 2007
Service MSSQLSERVER with parameters '-m SqlSetup -Q -qSQL_Latin1_General_CP1_CI_AS -T4022 -T3659 -T3610 -T4010' is being started at Tue Aug 28 01:01:33 2007
Attempt to start service when it is already running
SQL service MSSQLSERVER started successfully waiting for SQL service to accept client connections
Service MSSQLSERVER started at Tue Aug 28 01:01:33 2007
Loaded DLL:
C:\WINDOWS\system32\Odbc32.dll
Version:
3.525.1117.0

SQL_ERROR (-1) in OdbcConnection::connect
sqlstate=28000, level=-1, state=-1, native_error=18456, msg=[Microsoft][SQL Server Native Client 10.0][SQL Server]Login failed for user 'sa'.

Error Code: 0x80074818 (18456)
Windows Error Text: Source File Name: lib\odbc_connection.cpp
Compiler Timestamp: Tue Jul 24 04:09:22 2007
Function Name: OdbcConnection::connect@.connect
Source Line Number: 148

I had the same problem when i installed MS Sql 2008.

I find the firewall deny the port (135) for SQL connecting.

After open the port of the firewall, i re-install sql successfully.

sql