When you download Visual Studio 2010 Express Edition you have to choose which version you want. In those choice you have the C# version and the web version. Both of them seem to be similar but have some different template. For example, you cannot create a ASP.NET website with the C# one and cannot create a Console Application with the web one.
It also have an other big difference and it’s the Databae Explorer. The C# version won’t let you connect to SQL Server. Only SQL Compact or SQL file.
Here are 2 screen shots of the two Data Explorer:
This is interesting because if you want to use SQL Profile you need to use the SQL server and not a file or a compact edition. The reason behind this is that Microsoft may have think that application usually does not require to have a direct access to the SQL server and because they try to cut functionality in each of the Express edition, the C# edition got this cut. However, it’s possible to create a website with a SQL Server because usually web server use SQL Server and not a SQL database file.