Use the aspnet_regsql.exe command line. See http://msdn.microsoft.com/en-us/library/ff648345.aspx . Excerpts:
Step 2. Install the membership database
Before you can use the SqlMembershipProvider, you must install the SQL Server membership database.
To install the membership database, log in to your server with an account that has authority to administer SQL Server (for example, an administrator account). Open a Visual Studio 2005 command prompt and run the following command:
aspnet_regsql.exe -E -S localhost -A m
Where:
-E indicates authentication using the Windows credentials of the current registered user. -S (server) indicates the name of the server on which the database will be installed or already installed. -A m indicates the addition of membership support. This creates the tables and saves the procedures required by the members of the provider. Note. The Aspnet_regsql tool is also used to set database items for other ASP.NET 2.0 features such as role management, Profile, Personalization Web Parts, and Web events. The other command line arguments perform database operations for these other functions. You can use Aspnet_regsql without any command line arguments using the wizard, which allows you to specify connection information for your SQL Server and install or remove database items for all supported features.
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