diff --git a/app/controllers/attachments_controller.rb b/app/controllers/attachments_controller.rb
index 495b0dde4..8a32ba81b 100644
--- a/app/controllers/attachments_controller.rb
+++ b/app/controllers/attachments_controller.rb
@@ -177,31 +177,14 @@ class AttachmentsController < ApplicationController
       candown = true
       unless params[:type] == 'history'
         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) || (course.is_public? && @file.publiced?)
-          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)
-          elsif @file.container.is_a?(Issue)
+          if @file.container.is_a?(Issue)
             course = @file.container.project
             candown = course.member?(current_user)
           elsif @file.container.is_a?(Journal)
             course = @file.container.issue.project
             candown = course.member?(current_user)
+          else
+            course = nil
           end
           tip_exception(403, "您没有权限进入") if course.present? && !candown
           tip_exception(403, "您没有权限进入") if @file.container.is_a?(ApplyUserAuthentication)
diff --git a/app/models/attachment.rb b/app/models/attachment.rb
index 553c1daf2..45ba882d0 100644
--- a/app/models/attachment.rb
+++ b/app/models/attachment.rb
@@ -6,11 +6,11 @@ class Attachment < ApplicationRecord
 
   belongs_to :container, polymorphic: true, optional: true
   belongs_to :author, class_name: "User", foreign_key: :author_id
-  belongs_to :course, foreign_key: :container_id, optional: true
-  has_many :attachment_group_settings, :dependent => :destroy
+  # belongs_to :course, foreign_key: :container_id, optional: true
+  # has_many :attachment_group_settings, :dependent => :destroy
   has_many :attachment_histories, -> { order(version: :desc) }, :dependent => :destroy
   # 二级目录
-  belongs_to :course_second_category, optional: true
+  # belongs_to :course_second_category, optional: true
 
   scope :by_filename_or_user_name,      -> (keywords) { joins(:author).where("filename like :search or LOWER(concat(users.lastname, users.firstname)) LIKE :search",
                                                         :search => "%#{keywords.split(" ").join('|')}%") unless keywords.blank? }
diff --git a/app/models/user.rb b/app/models/user.rb
index f26fcb094..a093665f3 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -91,7 +91,7 @@ class User < ApplicationRecord
   # Groups and active users
   scope :active, lambda { where(status: STATUS_ACTIVE) }
   scope :like, lambda { |keywords|
-    where("LOWER(concat(lastname, firstname, login)) LIKE ?", "%#{keywords.split(" ").join('|')}%") unless keywords.blank?
+    where("LOWER(concat(lastname, firstname, login, mail)) LIKE ?", "%#{keywords.split(" ").join('|')}%") unless keywords.blank?
   }
 
   attr_accessor :password, :password_confirmation