diff --git a/app/views/contests/show_attendingcontest.html.erb b/app/views/contests/show_attendingcontest.html.erb
index d6f614db1..7818f5fb3 100644
--- a/app/views/contests/show_attendingcontest.html.erb
+++ b/app/views/contests/show_attendingcontest.html.erb
@@ -260,7 +260,9 @@
                   ：</strong><%= format_time c_project.created_at %></span>
                 <span style="padding-left: 240px"><strong><%= l(:label_attendingcontest_spoksman) %>
                   <!-- modified by zjc 添加超链接 -->
+                  <% unless c_project.nil? || c_project.user.nil? %>
                   ：</strong><%= link_to c_project.user.name,user_path(c_project.user) %></span>
+                  <% end %>
               </div>
 
               <div style="padding-left: 68px">
@@ -295,7 +297,9 @@
                   ：</strong><%= format_time c_softapplication.created_at %></span>
                 <span style="padding-left: 240px"><strong><%= l(:label_attendingcontest_spoksman) %>
                   <!-- modified by zjc 添加超链接 -->
+                  <% unless c_softapplication.nil? || c_softapplication.softapplication.nil? || c_softapplication.softapplication.user.nil?  %>
                   ：</strong><%= link_to c_softapplication.softapplication.user.name,user_path(c_softapplication.softapplication.user) %></span>
+                  <% end %>
               </div>
 
               <!--获奖及教师评奖-->
diff --git a/app/views/layouts/base_courses.html.erb b/app/views/layouts/base_courses.html.erb
index adedb66c5..5ab0a98a9 100644
--- a/app/views/layouts/base_courses.html.erb
+++ b/app/views/layouts/base_courses.html.erb
@@ -178,7 +178,7 @@
         </tr>
         <!-- end -->
 
-        <% unless @course.teacher.user_extensions.nil? %>
+        <% unless @course.teacher.user_extensions.nil? || @course.teacher.user_extensions.school.nil? %>
             <tr>
               <td valign="top" style="padding-left: 8px;"><%= l(:label_teacher_work_unit) %> :</td>
               <!-- modified by zjc 教师单位添加超链接 -->
diff --git a/app/views/layouts/base_homework.html.erb b/app/views/layouts/base_homework.html.erb
index 88190d536..ce9671ad1 100644
--- a/app/views/layouts/base_homework.html.erb
+++ b/app/views/layouts/base_homework.html.erb
@@ -116,7 +116,9 @@
                                           <tr>
                                             <td valign="top" style="padding-left: 8px;"><%= l(:label_teacher_work_unit) %> :</td>
                                             <!-- modified by zjc 有@user.user_extensions.occupation改为 @user.user_extensions.school 并添加超链接 -->
+                                            <% unless  @user.user_extensions.nil? ||  @user.user_extensions.school.nil? %>
                                             <td class="font_lighter_sidebar"><%= link_to @user.user_extensions.school,options={:controller => 'welcome',:action => 'course',:school_id => @user.user_extensions.school.id}, html_options={:method => 'get'} %></td>
+                                            <% end %>
                                           </tr>
                                         </table>
                                       </div>