diff --git a/app/controllers/attachments_controller.rb b/app/controllers/attachments_controller.rb
index 8eb7ffebc..a6c74818c 100644
--- a/app/controllers/attachments_controller.rb
+++ b/app/controllers/attachments_controller.rb
@@ -4,14 +4,13 @@
 class AttachmentsController < ApplicationController
   before_action :require_login, :check_auth, except: [:show]
   before_action :find_file, only: %i[show destroy]
+  before_action :attachment_candown, only: [:show]
 
   include ApplicationHelper
 
   def show
     # 1. 优先跳到cdn
     # 2. 如果没有cdn，send_file
-    candown = attachment_candown @file
-    tip_exception("您没有权限下载该附件") if !candown
     if @file.cloud_url.present?
       update_downloads(@file)
       redirect_to @file.cloud_url and return
@@ -160,32 +159,32 @@ class AttachmentsController < ApplicationController
     edu_setting('public_cdn_host') + "/" + path
   end
 
-  def attachment_candown attachment
-    return true if current_user.admin? || current_user.business?
-    candown = false
-    if attachment.container && current_user.logged?
-      # 课堂资源、作业、毕设相关资源的权限判断
-      if attachment.container.is_a?(Course)
-        course = attachment.container
-        candown = current_user.member_of_course?(course) || attachment.is_public == 1
-      elsif attachment.container.is_a?(HomeworkCommon) || attachment.container.is_a?(GraduationTask) || attachment.container.is_a?(GraduationTopic)
-        course = attachment.container&.course
-      elsif attachment.container.is_a?(StudentWork)
-        course = attachment.container&.homework_common&.course
-      elsif attachment.container.is_a?(StudentWorksScore)
-        course = attachment.container&.student_work&.homework_common&.course
-      elsif attachment.container.is_a?(GraduationWork)
-        course = attachment.container&.graduation_task&.course
-      elsif attachment.container.is_a?(GraduationWorkScore)
-        course = attachment.container&.graduation_work&.graduation_task&.course
-      else
-        candown = true
-      end
-
-      candown = !candown && course.present? ? current_user.member_of_course?(course) : candown
-    else
+  def attachment_candown
+    unless current_user.admin? || current_user.business?
       candown = true
+      if @file.container && current_user.logged?
+        # 课堂资源、作业、毕设相关资源的权限判断
+        if @file.container.is_a?(Course)
+          course = @file.container
+          candown = current_user.member_of_course?(course) || @file.is_public == 1
+        elsif @file.container.is_a?(HomeworkCommon) || @file.container.is_a?(GraduationTask) || @file.container.is_a?(GraduationTopic)
+          course = @file.container&.course
+          candown = current_user.member_of_course?(course)
+        elsif @file.container.is_a?(StudentWork)
+          course = @file.container&.homework_common&.course
+          candown = current_user.member_of_course?(course)
+        elsif @file.container.is_a?(StudentWorksScore)
+          course = @file.container&.student_work&.homework_common&.course
+          candown = current_user.member_of_course?(course)
+        elsif @file.container.is_a?(GraduationWork)
+          course = @file.container&.graduation_task&.course
+          candown = current_user.member_of_course?(course)
+        elsif @file.container.is_a?(GraduationWorkScore)
+          course = @file.container&.graduation_work&.graduation_task&.course
+          candown = current_user.member_of_course?(course)
+        end
+        tip_exception(403, "您没有权限进入") if course.present? && !candown
+      end
     end
-    candown
   end
 end
diff --git a/public/react/src/modules/page/MainContent.js b/public/react/src/modules/page/MainContent.js
index c03d49351..601c002a9 100644
--- a/public/react/src/modules/page/MainContent.js
+++ b/public/react/src/modules/page/MainContent.js
@@ -114,7 +114,7 @@ class MainContent extends Component {
 																?
 																readRepoTimeout === true ? <div className="readRepoFailed">
 																	代码加载失败，<a className="retry" 
-																		onClick={() => this.props.fetchRepositoryCode(this.props, null, null, true)}>重试</a>
+																		onClick={() => this.props.fetchRepositoryCode(this.props, null, null, true, true)}>重试</a>
 																</div> :
 						              			<React.Fragment>
 												  	<div style={{display: (codeLoading ? 'block' : 'none'), textAlign: 'center'}}>
diff --git a/public/react/src/modules/page/MainContentContainer.js b/public/react/src/modules/page/MainContentContainer.js
index d24a5cefb..a437391d6 100644
--- a/public/react/src/modules/page/MainContentContainer.js
+++ b/public/react/src/modules/page/MainContentContainer.js
@@ -235,7 +235,7 @@ class MainContentContainer extends Component {
     }
 
     // arg_path 点击文件目录树时，传入的点击节点对应的path
-	fetchRepositoryCode( props, arg_path, type, isRetry) {
+	fetchRepositoryCode( props, arg_path, type, isRetry, retryAndRefresh) {
     	const { challenge, showSnackbar, game, shixun, myshixun, hide_code } = props ? props : this.props;
 		if (shixun.vnc == true) {
 			// vnc模式下不需要加载代码
@@ -293,6 +293,10 @@ class MainContentContainer extends Component {
 			//     that._cancel = c;
 			// })
     	}).then((fetchRepositoryCodeResponse) => {
+				if (retryAndRefresh && fetchRepositoryCodeResponse.data.content) {
+					window.location.reload()
+					return;
+				}
 				// 空字符串还是正常切换
 				if (fetchRepositoryCodeResponse.data.status == 0) {
 					readingRepoTimes = readingRepoTimes + 1;