diff --git a/src/Volo.Abp.AspNetCore.Mvc.UI/wwwroot/libs/abp/abp.jquery.js b/src/Volo.Abp.AspNetCore.Mvc.UI/wwwroot/libs/abp/abp.jquery.js
index 38b4c3cd0f..c70a78d457 100644
--- a/src/Volo.Abp.AspNetCore.Mvc.UI/wwwroot/libs/abp/abp.jquery.js
+++ b/src/Volo.Abp.AspNetCore.Mvc.UI/wwwroot/libs/abp/abp.jquery.js
@@ -156,33 +156,33 @@
                     abp.ui.clearBusy(options.blockUI);
                 }
             }
-        },
-
-        ajaxSendHandler: function (event, request, settings) {
-            var token = abp.security.antiForgery.getToken();
-            if (!token) {
-                return;
-            }
-
-            if (!settings.headers || settings.headers[abp.security.antiForgery.tokenHeaderName] === undefined) {
-                request.setRequestHeader(abp.security.antiForgery.tokenHeaderName, token);
-            }
-        }
-    });
-
-    $(document).ajaxSend(function (event, request, settings) {
-        return abp.ajax.ajaxSendHandler(event, request, settings);
+        }//,
+
+        //ajaxSendHandler: function (event, request, settings) {
+        //    var token = abp.security.antiForgery.getToken();
+        //    if (!token) {
+        //        return;
+        //    }
+
+        //    if (!settings.headers || settings.headers[abp.security.antiForgery.tokenHeaderName] === undefined) {
+        //        request.setRequestHeader(abp.security.antiForgery.tokenHeaderName, token);
+        //    }
+        //}
     });
 
-    abp.event.on('abp.dynamicScriptsInitialized', function () {
-        abp.ajax.defaultError.message = abp.localization.abpWeb('DefaultError');
-        abp.ajax.defaultError.details = abp.localization.abpWeb('DefaultErrorDetail');
-        abp.ajax.defaultError401.message = abp.localization.abpWeb('DefaultError401');
-        abp.ajax.defaultError401.details = abp.localization.abpWeb('DefaultErrorDetail401');
-        abp.ajax.defaultError403.message = abp.localization.abpWeb('DefaultError403');
-        abp.ajax.defaultError403.details = abp.localization.abpWeb('DefaultErrorDetail403');
-        abp.ajax.defaultError404.message = abp.localization.abpWeb('DefaultError404');
-        abp.ajax.defaultError404.details = abp.localization.abpWeb('DefaultErrorDetail404');
-    });
+    //$(document).ajaxSend(function (event, request, settings) {
+    //    return abp.ajax.ajaxSendHandler(event, request, settings);
+    //});
+
+    //abp.event.on('abp.dynamicScriptsInitialized', function () {
+    //    abp.ajax.defaultError.message = abp.localization.abpWeb('DefaultError');
+    //    abp.ajax.defaultError.details = abp.localization.abpWeb('DefaultErrorDetail');
+    //    abp.ajax.defaultError401.message = abp.localization.abpWeb('DefaultError401');
+    //    abp.ajax.defaultError401.details = abp.localization.abpWeb('DefaultErrorDetail401');
+    //    abp.ajax.defaultError403.message = abp.localization.abpWeb('DefaultError403');
+    //    abp.ajax.defaultError403.details = abp.localization.abpWeb('DefaultErrorDetail403');
+    //    abp.ajax.defaultError404.message = abp.localization.abpWeb('DefaultError404');
+    //    abp.ajax.defaultError404.details = abp.localization.abpWeb('DefaultErrorDetail404');
+    //});
 
 })(jQuery);
\ No newline at end of file
diff --git a/src/Volo.Abp.Http/Volo/Abp/Http/Modeling/ReturnValueApiDescriptionModel.cs b/src/Volo.Abp.Http/Volo/Abp/Http/Modeling/ReturnValueApiDescriptionModel.cs
index 9dbdd40edb..001bd1b9c9 100644
--- a/src/Volo.Abp.Http/Volo/Abp/Http/Modeling/ReturnValueApiDescriptionModel.cs
+++ b/src/Volo.Abp.Http/Volo/Abp/Http/Modeling/ReturnValueApiDescriptionModel.cs
@@ -1,4 +1,5 @@
 using System;
+using Volo.Abp.Threading;
 
 namespace Volo.Abp.Http.Modeling
 {
@@ -9,14 +10,14 @@ namespace Volo.Abp.Http.Modeling
 
         private ReturnValueApiDescriptionModel()
         {
-            
+
         }
 
         public static ReturnValueApiDescriptionModel Create(Type type)
         {
             return new ReturnValueApiDescriptionModel
             {
-                TypeAsString = type.GetFullNameWithAssemblyName()
+                TypeAsString = AsyncHelper.UnwrapTask(type).GetFullNameWithAssemblyName()
             };
         }
     }
diff --git a/src/Volo.Abp.Identity.Application/Volo/Abp/Identity/IdentityRoleAppService.cs b/src/Volo.Abp.Identity.Application/Volo/Abp/Identity/IdentityRoleAppService.cs
index 99d454bc78..08b2ff4faa 100644
--- a/src/Volo.Abp.Identity.Application/Volo/Abp/Identity/IdentityRoleAppService.cs
+++ b/src/Volo.Abp.Identity.Application/Volo/Abp/Identity/IdentityRoleAppService.cs
@@ -68,7 +68,12 @@ namespace Volo.Abp.Identity
 
         public async Task DeleteAsync(Guid id)
         {
-            var role = await _roleManager.GetByIdAsync(id);
+            var role = await _roleManager.FindByIdAsync(id.ToString());
+            if (role == null)
+            {
+                return;
+            }
+
             await _roleManager.DeleteAsync(role);
         }
     }
diff --git a/src/Volo.Abp.Identity.Application/Volo/Abp/Identity/IdentityUserAppService.cs b/src/Volo.Abp.Identity.Application/Volo/Abp/Identity/IdentityUserAppService.cs
index 7b9425018c..1f853b5822 100644
--- a/src/Volo.Abp.Identity.Application/Volo/Abp/Identity/IdentityUserAppService.cs
+++ b/src/Volo.Abp.Identity.Application/Volo/Abp/Identity/IdentityUserAppService.cs
@@ -62,7 +62,12 @@ namespace Volo.Abp.Identity
 
         public async Task DeleteAsync(Guid id)
         {
-            var user = await _userManager.GetByIdAsync(id);
+            var user = await _userManager.FindByIdAsync(id.ToString());
+            if (user == null)
+            {
+                return;
+            }
+
             CheckIdentityErrors(await _userManager.DeleteAsync(user));
         }
 
diff --git a/src/Volo.Abp/Volo/Abp/Threading/AsyncHelper.cs b/src/Volo.Abp/Volo/Abp/Threading/AsyncHelper.cs
index bf6b5e060d..2b40cd6790 100644
--- a/src/Volo.Abp/Volo/Abp/Threading/AsyncHelper.cs
+++ b/src/Volo.Abp/Volo/Abp/Threading/AsyncHelper.cs
@@ -17,8 +17,36 @@ namespace Volo.Abp.Threading
         /// <param name="method">A method to check</param>
         public static bool IsAsync([NotNull] this MethodInfo method)
         {
-            return method.ReturnType == typeof(Task) ||
-                   (method.ReturnType.GetTypeInfo().IsGenericType && method.ReturnType.GetGenericTypeDefinition() == typeof(Task<>));
+            Check.NotNull(method, nameof(method));
+
+            return method.ReturnType.IsTaskOrTaskOfT();
+        }
+
+        public static bool IsTaskOrTaskOfT([NotNull] this Type type)
+        {
+            return type == typeof(Task) || type.GetTypeInfo().IsGenericType && type.GetGenericTypeDefinition() == typeof(Task<>);
+        }
+
+        /// <summary>
+        /// Returns void if given type is Task.
+        /// Return T, if given type is Task{T}.
+        /// Returns given type otherwise.
+        /// </summary>
+        public static Type UnwrapTask([NotNull] Type type)
+        {
+            Check.NotNull(type, nameof(type));
+
+            if (type == typeof(Task))
+            {
+                return typeof(void);
+            }
+
+            if (type.GetTypeInfo().IsGenericType && type.GetGenericTypeDefinition() == typeof(Task<>))
+            {
+                return type.GenericTypeArguments[0];
+            }
+
+            return type;
         }
 
         /// <summary>