I've tried to attach it using the SQL Server 2005 SMS but I'm getting the following error:

Attach database failed for Server 'Coral'.  (Microsoft.SqlServer.Smo)

ADDITIONAL INFORMATION:

An exception occurred while executing a Transact-SQL statement or batch. (Microsoft.SqlServer.ConnectionInfo)

Unable to open the physical file "C:\DotNetNuke_Build\Website\App_Data\Database2_log.ldf". Operating system error 2: "2(The system cannot find the file specified.)". (Microsoft SQL Server, Error: 5120)

Please note that even though I've tried to attach Database.mdf, the error refers to Database2_log.ldf.
Also, regardless of where my Database.mdf is located on the disk, the message continues to refer to folder "C:\DotNetNuke_Build\App_data\". Where is the Database_log.ldf? I cann't find it anywere?

Can someone please tell me what I'm doing wrong?

I've followed the instructions but the database is empty (nothing DNN specific, just System tables, stored procedures, etc)

Can anyone explain what Database.mdf contains and how to get it loaded in SQL 2005 SMS?

Jon, Sebastien,

Thanks both of you for the reply. Looking at the web.config, I can see now that only SQL Express connection string uses Database.mdf.

Question is: what is in that database, and why is it needed by the Express and not the Full version of SQL?

I could probably find out myself by loading Express on my machine. However, that would imply first removing the Full SQL &Visual Studio, then reinstalling them again to keep them in sink. I would like to avoid this if possible.