Getting SQL database error with MVC3 website - asp.net-mvc-3

Question

So I have created a MVC3 (Razor) Website in Visual Studio 2010. Now I want to publish it to a server but keep getting the following error message after I have published and uploaded files to server:
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)
Stack Trace
[SqlException (0x80131904): 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)]
System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +5103182
System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning() +260
System.Data.SqlClient.TdsParser.Connect(ServerInfo serverInfo, SqlInternalConnectionTds connHandler, Boolean ignoreSniOpenTimeout, Int64 timerExpire, Boolean encrypt, Boolean trustServerCert, Boolean integratedSecurity, Boolean withFailover) +389
System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, TimeoutTimer timeout, SqlConnection owningObject, Boolean withFailover) +197
System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(ServerInfo serverInfo, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, TimeoutTimer timeout) +963
System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, TimeoutTimer timeout, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance) +195
System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance) +316
System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection) +5119675
System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options) +33
System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject) +524
System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject) +66
System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) +479
System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +108
System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +126
System.Data.SqlClient.SqlConnection.Open() +125
WebMatrix.Data.Database.EnsureConnectionOpen() +44
WebMatrix.Data.<QueryInternal>d__0.MoveNext() +71
System.Linq.Enumerable.FirstOrDefault(IEnumerable`1 source) +4231764
WebMatrix.Data.Database.QuerySingle(String commandText, Object[] args) +103
WebMatrix.WebData.SimpleMembershipProvider.CheckTableExists(Database db, String tableName) +59
WebMatrix.WebData.SimpleMembershipProvider.CreateTablesIfNeeded() +55
WebMatrix.WebData.WebSecurity.InitializeMembershipProvider(SimpleMembershipProvider sMembership, DatabaseConnectionInfo connect, String userTableName, String userIdColumn, String userNameColumn, Boolean createTables) +73
WebMatrix.WebData.WebSecurity.InitializeProviders(DatabaseConnectionInfo connect, String userTableName, String userIdColumn, String userNameColumn, Boolean autoCreateTables) +51
WebMatrix.WebData.WebSecurity.InitializeDatabaseConnection(String connectionStringName, String userTableName, String userIdColumn, String userNameColumn, Boolean autoCreateTables) +51
ASP._Page__AppStart_cshtml.Execute() in *:\HostingSpaces\***\***.com\wwwroot\_AppStart.cshtml:3
System.Web.WebPages.ApplicationStartPage.<ExecuteInternal>b__3() +65
System.Web.WebPages.ApplicationStartPage.<GetSafeExecuteStartPageThunk>b__a(Action action) +7
System.Web.WebPages.ApplicationStartPage.ExecuteInternal() +78
System.Web.WebPages.ApplicationStartPage.ExecuteStartPageInternal(HttpApplication application, Action`1 monitorFile, Func`2 fileExists, Func`2 createInstance, IEnumerable`1 supportedExtensions) +202
System.Web.WebPages.ApplicationStartPage.ExecuteStartPage(HttpApplication application, Action`1 monitorFile, Func`2 fileExists, Func`2 createInstance, IEnumerable`1 supportedExtensions) +41
[HttpException (0x80004005): Exception of type 'System.Web.HttpException' was thrown.]
System.Web.WebPages.ApplicationStartPage.ExecuteStartPage(HttpApplication application, Action`1 monitorFile, Func`2 fileExists, Func`2 createInstance, IEnumerable`1 supportedExtensions) +88
System.Web.WebPages.ApplicationStartPage.ExecuteStartPage(HttpApplication application) +287
System.Web.WebPages.WebPageHttpModule.StartApplication(HttpApplication application, Action`1 executeStartPage, EventHandler applicationStart) +113
System.Web.WebPages.WebPageHttpModule.StartApplication(HttpApplication application) +71
System.Web.WebPages.WebPageHttpModule.Init(HttpApplication application) +217
System.Web.HttpApplication.RegisterEventSubscriptionsWithIIS(IntPtr appContext, HttpContext context, MethodInfo[] handlers) +517
System.Web.HttpApplication.InitSpecial(HttpApplicationState state, MethodInfo[] handlers, IntPtr appContext, HttpContext context) +194
System.Web.HttpApplicationFactory.GetSpecialApplicationInstance(IntPtr appContext, HttpContext context) +339
System.Web.Hosting.PipelineRuntime.InitializeApplication(IntPtr appContext) +253
[HttpException (0x80004005): Exception of type 'System.Web.HttpException' was thrown.]
System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +9090876
System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +97
System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context) +256
This is my Web.Config file:
<configuration>
<system.web>
<customErrors mode="Off"/>
<authentication mode="Forms" />
<roleManager enabled="true" />
<pages maintainScrollPositionOnPostBack="true">
<controls>
<add tagPrefix="ajaxToolkit" assembly="AjaxControlToolkit" namespace="AjaxControlToolkit" />
</controls>
</pages>
<compilation debug="true" targetFramework="4.0">
<assemblies>
<add assembly="System.Security, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A" />
<add assembly="System.Data.Entity, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089" />
<add assembly="System.Data.Entity.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089" />
</assemblies>
<buildProviders>
<add extension=".edmx" type="System.Data.Entity.Design.AspNet.EntityDesignerBuildProvider" />
</buildProviders>
</compilation>
</system.web>
<connectionStrings>
<add name="WhimsicalFurnishingEntities" connectionString="metadata=res://*/App_Code.WhimsicalFurnishingModel.csdl|res://*/App_Code.WhimsicalFurnishingModel.ssdl|res://*/App_Code.WhimsicalFurnishingModel.msl;provider connection string="data source=localhost\sqlexpress;Database=DBNAME;Uid=USERNAME;Password=PASSWORD;integrated security=True;user instance=True;multipleactiveresultsets=True;App=EntityFramework"" providerName="System.Data.EntityClient" />
Is there something I am missing to add in my project? I am sure the data source is correct with localhost\sqlexpress.
Thank You

Answer 1

I am assuming you are publishing this to a different server like a virtual private host? If so, it is very weird that the datasource is sqlexpress.
Localhost\sqlexpress is for SQLServer Express which is typically installed on developer machines, if it's on a production server you will usually have SQLServer Enterprise or something else.

Answer 2

If you have provided the correct database connection string with SQL Server Instance, then you may restart your database server service. Then again try to publish your site. Please ask if it not worked for you.