After installing Visual Studio 2010 with SQL Server Express 2008 in Windows 7, then you might face the problem that I am facing now, cannot install SQL Management Studio 2008 to the Windows 7 machine and you wish to remotely access using the SQL Management Studio that have been installed in other machine. Somehow you realized SQL Authentication is needed. That is how the below actions will help.
Change your registry key value LoginMode to 2 by following the registry key path below:
HKEY_LOCAL_MACHINESOFTWAREMicrosoftMicrosoft SQL ServerMSSQL10.SQLEXPRESSMSSQLServerCurrentVersion
To open Registry Editor, click Start, click Run, type regedt32, and then click OK.
To use the SQL Server, authenticate first to enable the sa account then set the password for sa account as below.
Restart SQL Server Express 2008 and try to login using sa account.
How to: Change Server Authentication Mode