Cita: <connectionStrings>
<add name="ConnectionString" connectionString="Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirector y|\ASPNETDB.MDF;Integrated Security=True;User Instance=True;" providerName="System.Data.SqlClient"/>
</connectionStrings>
De que forma lo provaste:
Código ASP:
Ver original<connectionStrings>
<remove name="LocalSqlServer" />
<add name="LocalSqlServer" connectionString="Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\ASPNETDB.MDF;Integrated Security=True;User Instance=True;" providerName="System.Data.SqlClient"/>
</connectionStrings>