The first place to look if you have trouble with the installation is the log files. The installation program maintains a log of the installation progress called sqlstp.log in the Winnt system directory. Reviewing the output of this log along with the system and application logs in Event Viewer will usually point you to the source of the problem. Common problems that come up after installation usually involve network connectivity or failure of the services to start.
Before banging your head against the wall troubleshooting SQL Server connectivity, make sure that network connectivity can be established using network tools appropriate to your protocol, such as ping for TCP/IP. If you can connect locally (which uses the shared memory library) but not from a client, ensure that the client and server net-libraries match.
If one or more services fail to start, check the application log in Event Viewer and the SQL Server log for the appropriate service. The most common cause of this type of error is an incorrect password for the service or a password that is set to expire on first logon. Try to log in with the account manually to ensure that it is configured correctly. If the account can log in, check that it is a member of the administrators group and that it has been granted the right to log on as a service. A good way to test if the problem is account related is to set the service to run as the local system account. If the service starts under this account, then the problem is related to the account you are using. It is also possible that a domain controller is not available to validate the account. This is not likely in production, but if you are testing SQL Server in the lab, the network for the lab is often isolated from the corporate network.