一般我們能過VS2005的SQL explorer來新增一個本地的MDF檔。也許你可能會出現下面這個問題：
Exception Details: System.Data.SqlClient.SqlException: The user instance login flag is not supported on this version of SQL Server. The connection will be closed.
透過搜尋。發現這裡有我們所需要的資訊：Error Message: The user instance login flag is not supported on this version of SQL Server. The connection will be closed
仔細分析Scott的回答：
"The issue is that User Instancing, which allows the auto allow creation of databases from code, isn't support on the full version of SQL 2005. That is a function of SQL Express only. The solution is to manually create the database in SQL Server 2005 and set a connection string to point to string. will also need to run aspnet_regsql.exe manually against the database if you
will be using any of the new built-in database features of ASP.NET v2.0."因此，如果我們不是使用的從MS下載下來的SQL Server 2005 Express，那我們只能過在SQL2005管理器上把MDF檔案加進去在連接它。
解決方法：在SQL2005管理器上，透過Attach（附加）本地的MDF檔案成功之後。在VS2005的sql explorer的連線即可。
以後繼續補充。
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