Could not load file or assembly ‘System.Net.Http’ or one of its dependencies. An attempt was made to load a program with an incorrect format.

[BadImageFormatException: Could not load file or assembly 'System.Net.Http' or one of its dependencies. An attempt was made to load a program with an incorrect format.]
   System.Reflection.RuntimeAssembly._nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks) +0
   System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, Evidence assemblySecurity, RuntimeAssembly reqAssembly, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks) +232
   System.Reflection.RuntimeAssembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean forIntrospection) +113
   System.Reflection.RuntimeAssembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean forIntrospection) +23
   System.Reflection.Assembly.Load(String assemblyString) +35
   System.Web.Configuration.CompilationSection.LoadAssemblyHelper(String assemblyName, Boolean starDirective) +49

[ConfigurationErrorsException: Could not load file or assembly 'System.Net.Http' or one of its dependencies. An attempt was made to load a program with an incorrect format.]
   System.Web.Configuration.CompilationSection.LoadAssemblyHelper(String assemblyName, Boolean starDirective) +762
   System.Web.Configuration.CompilationSection.LoadAllAssembliesFromAppDomainBinDirectory() +259
   System.Web.Configuration.CompilationSection.LoadAssembly(AssemblyInfo ai) +167
   System.Web.Compilation.BuildManager.GetReferencedAssemblies(CompilationSection compConfig) +238
   System.Web.Compilation.BuildManager.GetPreStartInitMethodsFromReferencedAssemblies() +78
   System.Web.Compilation.BuildManager.CallPreStartInitMethods(String preStartInitListPath, Boolean& isRefAssemblyLoaded) +334
   System.Web.Compilation.BuildManager.ExecutePreAppStart() +178
   System.Web.Hosting.HostingEnvironment.Initialize(ApplicationManager appManager, IApplicationHost appHost, IConfigMapPathFactory configMapPathFactory, HostingEnvironmentParameters hostingParameters, PolicyLevel policyLevel, Exception appDomainCreationException) +746

[HttpException (0x80004005): Could not load file or assembly 'System.Net.Http' or one of its dependencies. An attempt was made to load a program with an incorrect format.]
   System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +552
   System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +122
   System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context) +737