SQL Connection Error when run application(Production Server)

Hi Everyone 

I'm getting the follwoing error  when I configure my Application in the production server 
It's working perfect in my machine :

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 tried all of the articals to enable the TCP/IP and allow remote access and so many 

but still it's not working form me I double checked my connectionString name and still the same error :

this is my Web.config code :

<?xml version="1.0"?><!--

  For more information on how to configure your ASP.NET application, please visit

  http://go.microsoft.com/fwlink/?LinkId=169433

  --><configuration>

<appSettings>

     <add key="CrystalImageCleaner-AutoStart" value="true" />

     <add key="CrystalImageCleaner-Sleep" value="60000" />

     <add key="CrystalImageCleaner-Age" value="120000" />

 </appSettings>

 <connectionStrings>

<add name="ApplicationServices" connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|\aspnetdb.mdf;User Instance=true" providerName="System.Data.SqlClient" />

<add name="SurveyConnectionString" connectionString="Data Source=TESTSRV;Initial Catalog=MYDB;User ID=***;Password=***" providerName="System.Data.SqlClient" />

   <add name="ADConnectionString"

       connectionString="LDAP://SRV1445.mom.eu"/>

 

 </connectionStrings>

 

    

    <system.web>

<httpHandlers>

<add path="Reserved.ReportViewerWebControl.axd" verb="*" type="Microsoft.Reporting.WebForms.HttpHandler, Microsoft.ReportViewer.WebForms, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" validate="false" />

<add verb="GET" path="CrystalImageHandler.aspx" type="CrystalDecisions.Web.CrystalImageHandler, CrystalDecisions.Web, Version=13.0.2000.0, Culture=neutral, PublicKeyToken=692fbea5521e1304" /></httpHandlers>

<customErrors mode="Off">

</customErrors>

<compilation debug="true" targetFramework="4.0">

<buildProviders>

<add extension=".rdlc" type="Microsoft.Reporting.RdlBuildProvider, Microsoft.ReportViewer.WebForms, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />

</buildProviders>

</compilation>

<authentication mode="Forms">

        <forms name=".ADAuthCookie" loginUrl="~/Account/Login.aspx" timeout="43200"/>

      </authentication>

      <authorization>

        <deny users="?"/>

        <allow users="*"/>

      </authorization>

       

<membership defaultProvider="MyADMembershipProvider">

<providers>

        <clear/>

        <add name="MyADMembershipProvider"

        type="System.Web.Security.ActiveDirectoryMembershipProvider,

        System.Web, Version=2.0.0.0, Culture=neutral,

        PublicKeyToken=b03f5f7f11d50a3a"

        connectionStringName="ADConnectionString"

        attributeMapUsername="sAMAccountName"/>

       </providers>

</membership>

<profile>

<providers>

<clear />

<add name="AspNetSqlProfileProvider" type="System.Web.Profile.SqlProfileProvider" connectionStringName="ApplicationServices" applicationName="/" />

</providers>

</profile>

<roleManager enabled="true">

<providers>

<clear />

<add connectionStringName="ApplicationServices" applicationName="/" name="AspNetSqlRoleProvider" type="System.Web.Security.SqlRoleProvider" />

<add applicationName="/" name="AspNetWindowsTokenRoleProvider" type="System.Web.Security.WindowsTokenRoleProvider" />

</providers>

</roleManager>

</system.web>

<system.webServer>

<modules runAllManagedModulesForAllRequests="true" />

<validation validateIntegratedModeConfiguration="false" />

<handlers>

<add name="ReportViewerWebControlHandler" preCondition="integratedMode" verb="*" path="Reserved.ReportViewerWebControl.axd" type="Microsoft.Reporting.WebForms.HttpHandler, Microsoft.ReportViewer.WebForms, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />

<add name="CrystalImageHandler.aspx_GET" verb="GET" path="CrystalImageHandler.aspx" type="CrystalDecisions.Web.CrystalImageHandler, CrystalDecisions.Web, Version=13.0.2000.0, Culture=neutral, PublicKeyToken=692fbea5521e1304" preCondition="integratedMode" /></handlers>

</system.webServer>

</configuration>