(Very old news, but I keep having to go back to this)
If your SQL client (ie: SQL Server Mangement Studio, Toad, Embarcadero, etc) can't connect to a MS SQL Server 2005 Express Edition installation, follow these steps:
Launch
SQL Server Configuration ManagerClick on
SQL Server 2005 Network ConfigurationClick on
Protocols for MSSERVER=>right click on TCP/IP=>propertiesClick on
Protocols, make sure it is enabledClick on
IP Addressesand make sure under each of theIP1,IP2andIPAll, that the port is1433Click on
SQL Native Client ConfigurationClick on
Client protocols=>TCP/IP=> right click =>Properties=> make sure theportis1433Right click on
Alias=>New alias=>Alias:any name. Port:1433.Server`: host name for the SQL Server Express instanceTry to connect
