I have VS 2008 Professional Edition. After the installation (which included SQL Server 2008), I decided to install SQL Server 2008 Express Edition with Advanced Tools (so I could get SQL Server Management Studio on it). So I uninstalled the SQL Express that came with VS 2008, and installed the standalone SQL Server Express 2008 version with advanced tools.

However, When I try to logon onto SQL Server Management Studio using:

.\SQLEXPRESS

as Server name and Windows Authentication as the authentication, I get the following message:

 TITLE: Connect to Server
 ------------------------------

 Cannot connect to .\SQLEXPRESS.

 ------------------------------ ADDITIONAL INFORMATION:

 A network-related or instance-specific
 error occurred while establishing a
 connection to SQL Server. The server
 was not found or was not accessible.
 Verify that the instance name is
 correct and that SQL Server is
 configured to allow remote
 connections. (provider: SQL Network
 Interfaces, error: 26 - Error Locating
 Server/Instance Specified) (Microsoft
 SQL Server, Error: -1)

 For help, click:
 http//go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&EvtSrc=MSSQLServer&EvtID=-1&LinkId=20476

 ------------------------------ BUTTONS:

 OK
 ------------------------------

Any suggestions on how to get it to work? I have tried disabling Windows Firewall as well and still no luck. I am using WIndows Vista and SQL Server 2008 Express SP1 Patch has also been applied recently.