Yesterday I deployed a MVC4 app to Winhost and got this error below when I clicked on “Log In” or “Register”, which I didn’t when deployed to local IIS.

A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)

I had seen such error before; mostly the error was due to some misspelled SQL server name or firewall blocking remote access, etc. I checked my SQL server connection strings for both SqlClient and Entities Framework model and were able to connect to the remote SQL db hosted at Winhost. When I submitted a support ticket to Winhost tech team, their server side log showed that my app tried to connect to a SQL Express instance which they don’t support. How strange was that? I do not use SQL Express and my database which contains the ASP.Net Membership objects resides on a full version local SQL Server, not Express. There is no place in my web.config that has anything to do with SQL Express instance. So I examined the Controller codes where the Log In link is clicked; here it was, the new “InitializeSimpleMembership” attribute on the AccountController class which was created automatically by my selecting the “Internet Application” MVC4 project template. This was something new introduced by MVC4 team at Microsoft, where a bunch of genius are always trying to come up with some dummy robot codes to  make everything so automatic – by “simply” looking for a SQL Express db to initiate the Membership provider for Web.Security; this “InitializeSimpleMembership” attribute, as it turns out, was the only culprit for all these non-simple headaches when you deploy your site to hosting server that usually do not support SQL Express. And there was no warning or error when I used the Publishing wizard from VS2012 to deploy the site to Winhost.

The fix? Simply commented out the attribute, as shown below,and re-deployed to Winhost; then everything works!

[Authorize]

  //[InitializeSimpleMembership]
    public class AccountController : Controller
    {
        //
        // GET: /Account/Login

        [AllowAnonymous]
        public ActionResult Login(string returnUrl)
        {
            ViewBag.ReturnUrl = returnUrl;
            return View();