By Default installation, remote connection is disabled.
If you have an issue to connect the MSSQL Management Studio to a remote MSSQL Server, you will need to change the following configration on the SQL Server Surface Area Configuration.
Enable remote named pipe or tcp: All programs | Microsoft SQL Server 2005| Configuration Tools | SQL Server Surface Area Configuration | Configuration for Services and Connections | Remote Connections, choose either enable TCP or Named Pipe or both.