Hi, all.
A bit new to web development but not new to software development.
Web application is using Telerik grid and upload controls. Everything is working as expected on development machine.
How it was deployed on the server: copied everything including bin folder to the server. Telerik.Web.UI.dll is there. File version-2011.1.315.40. Product version -2011.1.315.40.
Checked app pools, frameworks are same for app pool and for web application.
When started on the server I am getting to login screen OK. Login screen is passed to next screen that is using Telerik control and there I am keep getting "Could not load file or assembly 'Telerik.Web.UI, Version=2011.1.315.40, Culture=neutral, PublicKeyToken=121fae78165ba3d4' or one of its dependencies. The system cannot find the file specified."

Thank you,
Alex.

<?xml version="1.0" encoding="UTF-8"?>
<!--
  For more information on how to configure your ASP.NET application, please visit
  http://go.microsoft.com/fwlink/?LinkId=169433
  -->
<configuration>
  <configSections>
    <sectionGroup name="applicationSettings" type="System.Configuration.ApplicationSettingsGroup, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
    </sectionGroup>
  </configSections>
  <connectionStrings>
    <add name="ApplicationServices" connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|\aspnetdb.mdf;User Instance=true" providerName="System.Data.SqlClient" />
  </connectionStrings>
  <system.web>
    <compilation debug="true" targetFramework="4.0">
      <assemblies>
  <add assembly="System.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A" />
  <add assembly="System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089" />
  <add assembly="System.Speech, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
  <add assembly="Telerik.Web.UI, Version=2011.1.315.40, Culture=neutral, PublicKeyToken=121fae78165ba3d4" />
   </assemblies>
    </compilation>
    <authentication mode="Forms">
      <forms loginUrl="~/Account/Login.aspx" timeout="2880" />
    </authentication>
    <membership>
      <providers>
        <clear />
        <add name="AspNetSqlMembershipProvider" type="System.Web.Security.SqlMembershipProvider" connectionStringName="ApplicationServices" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="false" requiresUniqueEmail="false" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="6" minRequiredNonalphanumericCharacters="0" passwordAttemptWindow="10" applicationName="/" />
      </providers>
    </membership>
    <profile>
      <providers>
        <clear />
        <add name="AspNetSqlProfileProvider" type="System.Web.Profile.SqlProfileProvider" connectionStringName="ApplicationServices" applicationName="/" />
      </providers>
    </profile>
    <roleManager defaultProvider="AspNetWindowsTokenRoleProvider">
      <providers>
        <clear />
        <add connectionStringName="ApplicationServices" applicationName="/" name="AspNetSqlRoleProvider" type="System.Web.Security.SqlRoleProvider" />
        <add applicationName="/" name="AspNetWindowsTokenRoleProvider" type="System.Web.Security.WindowsTokenRoleProvider" />
      </providers>
    </roleManager>
    <httpHandlers>
      <add path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource" verb="*" validate="false" />
      <add verb="*" path="Telerik.RadUploadProgressHandler.ashx" type="Telerik.Web.UI.Upload.RadUploadProgressHandler,Telerik.Web.UI" />
    </httpHandlers>
    <httpModules>
      <!--<add name="RadUploadModule" type="Telerik.Web.UI.RadUploadHttpModule, Telerik.Web.UI" /> -->
 <add name="RadUploadModule" type="Telerik.Web.UI.RadUploadHttpModule, Telerik.Web.UI, Version=2011.1.315.40, Culture=neutral, PublicKeyToken=121fae78165ba3d4 " />
 </httpModules>
  </system.web>
  <system.webServer>
    <modules>
      <add name="ScriptModule" preCondition="integratedMode" type="System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
      <!-- *******  Register the RadUploadModule for IIS 7  ****** --><!--
      <add name="RadUploadModule" preCondition="integratedMode" type="Telerik.Web.UI.RadUploadHttpModule" />-->
      <add name="RadUploadModule" type="Telerik.Web.UI.RadUploadHttpModule, Telerik.Web.UI" preCondition="managedHandler" />
    </modules>
    <validation validateIntegratedModeConfiguration="false" />
    <handlers>
      <add name="Telerik_Web_UI_WebResource_axd" verb="*" preCondition="integratedMode" path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource" />
      <!-- *******  Register the RadUploadProgressHandler for IIS 7  ****** -->
      <!--<add name="Telerik_RadUploadProgressHandler_ashx" verb="*" preCondition="integratedMode" path="Telerik.RadUploadProgressHandler.ashx" type="Telerik.Web.UI.RadUploadProgressHandler" />-->
      <!--<add name="Telerik.RadUploadProgressHandler.ashx_*" path="Telerik.RadUploadProgressHandler.ashx" verb="*" type="Telerik.Web.UI.Upload.RadUploadProgressHandler, Telerik.Web.UI" preCondition="integratedMode,runtimeVersionv2.0" />-->
    <add name="Telerik.RadUploadProgressHandler.ashx_*" verb="*" path="Telerik.RadUploadProgressHandler.ashx" type="Telerik.Web.UI.RadUploadProgressHandler, Telerik.Web.UI, Version =2011.1.315.40, Culture=neutral, PublicKeyToken =121fae78165ba3d4 " />
</handlers>
        <defaultDocument>
            <files>
                <add value="login.aspx" />
            </files>
        </defaultDocument>
  </system.webServer>
</configuration>

I think I fixed it.
I have a web services folder under web application and this web services folder aslo have bin folder.
I placed Telerik.Web.UI.dll under bin under web services folder and it started to give me another error security-related.