Visual Basic and SQL Server Express Connection

When I use the following code to connect to SQL Server Express it work on Windows 8 the Windows my Visual Basic program is written on. But when I publish my application and install it on a Windows 7 system I receive error message when I attempt to connect to the SQL Server Express.
Dim connectionStrig as String = "data sorce=locatlhost\sqlexpress;initial catelog=MASTER," & "integrated securiyth= true"
Dim conection_Intial as new Sqlconnection() Connection_Initial.connectionString = connectionstring
The above code work fine on Windows 8
========================================================================= I have included  Framework 4.5 and SQL Server LocalDB as preprequisites when I publish my application and they are installed on Windows 7 after I reboot Windows 7 as per instructions of the ClickOnce Install message.
After I reboot Windows 7 system and e ...