I'm working on a Windows Forms application that interacts with a Sql Compact database file created by SQL Server 2005. This application was originally developed in Visual Studio 2005 but was recently converted to a Visual Studio 2008 solution.

In regards to Sql Compact, we made sure the references were all still set to the assemblies that handle the 2005 version of Sql Compact rather than Sql Compact 3.5. Having done this, the application still runs just as it should - it will still interact with the Compact database, perform synchronization operations, etc.

However, I just discovered today that Visual Studio tools such as the DataSet Designer do not play well with a Sql Compact database file of an older version than 3.5. If I go to the New Connection... wizard, the only Sql Compact Data Source / Data Provider are for Sql Compact 3.5. I assume that Visual Studio 2008 just doesn't include the data provider for the older version of Sql Compact by default.

Is there a way you can add the old version of Sql Compact to the list of "Data Sources" for the connection wizard? To see exactly what I'm referring to, click on the Tools menu of Visual Studio 2008 and click Connect to Database... In the window that comes up, click Change... next to the Data source setting. From this dialog there is no way I can select the earlier version of Sql Compact - only 3.5 is available.

Maybe I need to add an assembly reference somewhere? Or copy some file(s) from my Visual Studio 2005 directory over to 2008? I would think there would have to be a way for Visual Studio 2008 to be able to interact with a Sql Compact database from Sql Server 2005.

To provide one more bit of detail, I discovered this problem when I went to my DataSet, right-clicked and tried to add a TableAdapter. The first screen that comes up says, "Choose Your Data Connection". If I leave it set to the Sql Compact connection that we've always used, I now get the following error when clicking the Next > button:

Failed to open a connection to the database

"The selected database was created with an earlier version of SQL Server Compact and needs to be upgraded to SQL Server Compact 3.5 before the connection can be opened or tested. Upgrade the database by creating a new data connection and completing the Add Connection dialog box."

Check the connection and try again.

The only problem here is that we still use Sql Server 2005, and if my understanding is correct, it does not produce subscription files that are compatible with Sql Compact 3.5. If I am wrong in this assumption, please correct me.

Any help you can provide is greatly appreciated. Thank you.