diff --git a/.gitignore b/.gitignore
index bc936c34c..31ecab95f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -23,3 +23,4 @@
 public/api_doc/
 /.metadata
 vendor/cache
+/files
diff --git a/files/2013/07/130722111340_2f0b01a362fe0cdd98bbadd22ea6e1cc.pptx b/files/2013/07/130722111340_2f0b01a362fe0cdd98bbadd22ea6e1cc.pptx
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diff --git a/files/2013/08/130810152034_bb9f0cd2d3f99d66798552a28cae27a6.doc b/files/2013/08/130810152034_bb9f0cd2d3f99d66798552a28cae27a6.doc
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diff --git a/files/2013/08/130813002701_Desert.jpg b/files/2013/08/130813002701_Desert.jpg
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diff --git a/files/2013/08/130827170642_1675b2d45e868443acb3447a529c1ace.txt b/files/2013/08/130827170642_1675b2d45e868443acb3447a529c1ace.txt
deleted file mode 100644
index 0faa795e7..000000000
--- a/files/2013/08/130827170642_1675b2d45e868443acb3447a529c1ace.txt
+++ /dev/null
@@ -1,4 +0,0 @@
-客户机操作系统：Ubuntu Linux（64位）
-虚拟机版本：8
-Cpu：2vcpu
-内存：4196MB
diff --git a/files/2013/08/130829095300_1675b2d45e868443acb3447a529c1ace.txt b/files/2013/08/130829095300_1675b2d45e868443acb3447a529c1ace.txt
deleted file mode 100644
index 0faa795e7..000000000
--- a/files/2013/08/130829095300_1675b2d45e868443acb3447a529c1ace.txt
+++ /dev/null
@@ -1,4 +0,0 @@
-客户机操作系统：Ubuntu Linux（64位）
-虚拟机版本：8
-Cpu：2vcpu
-内存：4196MB
diff --git a/files/2013/09/130909091918_twurn.com_.png b/files/2013/09/130909091918_twurn.com_.png
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diff --git a/files/2013/09/130909102300_twurn.com_.png b/files/2013/09/130909102300_twurn.com_.png
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diff --git a/files/2013/09/130909102607_48a3823e1ee72a1a06a62cbdcb4a5cd0.txt b/files/2013/09/130909102607_48a3823e1ee72a1a06a62cbdcb4a5cd0.txt
deleted file mode 100644
index 4eeb9c90d..000000000
--- a/files/2013/09/130909102607_48a3823e1ee72a1a06a62cbdcb4a5cd0.txt
+++ /dev/null
@@ -1,7 +0,0 @@
-<!-- add by huang -->
-		<% if(@project.project_type)%>
-			<%= content_tag('span', "#{l(:field_tea_name)}: ") %>
-		<% else %>
-			<%= content_tag('span', "#{l(:default_role_manager)}: ") %>
-		<% end %>
-		<!-- end  -->
\ No newline at end of file
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diff --git a/files/2013/09/130913152553_d53d97d93a897698e1b597ba567568fe.exe b/files/2013/09/130913152553_d53d97d93a897698e1b597ba567568fe.exe
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diff --git a/files/2013/09/130913205349_XMP.exe b/files/2013/09/130913205349_XMP.exe
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diff --git a/files/2013/09/130913211043_d53d97d93a897698e1b597ba567568fe.exe b/files/2013/09/130913211043_d53d97d93a897698e1b597ba567568fe.exe
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diff --git a/files/2013/09/130916200529_heart.svg b/files/2013/09/130916200529_heart.svg
deleted file mode 100644
index 6cc8390b2..000000000
--- a/files/2013/09/130916200529_heart.svg
+++ /dev/null
@@ -1,9 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- Generator: Adobe Illustrator 14.0.0, SVG Export Plug-In . SVG Version: 6.00 Build 43363)  -->
-<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.0//EN" "http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd">
-<svg version="1.0" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
-	 width="100px" height="93.615px" viewBox="0 0 100 93.615" enable-background="new 0 0 100 93.615" xml:space="preserve">
-<path d="M99.866,23.353C98.533,10.235,87.456,0,73.988,0C63.193,0,53.938,6.575,50,15.937C46.062,6.575,36.807,0,26.013,0
-	C12.544,0,1.466,10.235,0.134,23.353C0.045,24.227,0,25.115,0,26.013c0,31.606,38.788,46.523,50,67.603h0
-	c11.212-21.079,50-35.996,50-67.603C100,25.115,99.955,24.227,99.866,23.353z"/>
-</svg>
diff --git a/files/2013/10/131007102834__my_course.html.erb b/files/2013/10/131007102834__my_course.html.erb
deleted file mode 100644
index 19acd49ac..000000000
--- a/files/2013/10/131007102834__my_course.html.erb
+++ /dev/null
@@ -1,68 +0,0 @@
-<div class="content_frame">
-	<% if @memberships.empty? %>
-		<% if @user != User.current %>
-		<p class="font_description">
-			<%= l(:label_project_course_un) %>
-		</p>
-		<% else %>
-		<p class="font_description">
-			<%= l(:label_project_course_unadd) %>
-			<% if User.current.user_extensions.identity == 0 %>
-			<%= link_to"#{l(:label_course_new)}",{:controller=>'projects',:action=>'new', :course => 1}, :class => 'icon icon-add' %>
-			<% end %>
-		</p>
-		<% end %>
-	<% else %>
-	<% if User.current.user_extensions.identity == 0 %>
-	<%= link_to"#{l(:label_course_new)}",{:controller=>'projects',:action=>'new', :course => 1}, :class => 'icon icon-add' %>
-	<% end %>
-	<ul class="user_project_sort">
-		<% for membership in @memberships %>
-		<li>
-			<table width="660" border="0" align="center" style="border-bottom: 1px dashed rgb(204, 204, 204); margin-bottom: 10px;font-size:14px;">
-				<tr>
-					<td colspan="2" valign="top" width="50" ><% if get_avatar?(membership.project)%>
-		<%= link_to image_tag(url_to_avatar(membership.project), :class => 'avatar'), project_path(membership.project) %>
-		<% else %>
-		<%= link_to image_tag('../images/avatars/Project/course.jpg',  :class => "avatar"), project_path(membership.project)%>
-		<% end %></td>
-					<td>
-					<table width="580" border="0">
-						<tr>
-							<td colspan="2" valign="top"><span><%= link_to_project(membership.project) %></span>
-								<span style="float: right"><%= l(:label_homework) %> (<span class=""><%= link_to (membership.project.homeworks.count), {:controller => 'projects', :action => 'homework', :id => membership.project.identifier} %></span>)
-								&nbsp;&nbsp;&nbsp;
-								<%= l(:label_course_news)%> (<span style="color: #ed8924"><%= link_to (membership.project.news.count), {:controller => 'news', :action => 'index', :project_id => membership.project.identifier} %></span>)
-								<!-- <%= l(:label_member)%>(<span style="color: #ed8924"><%= link_to (membership.project.members.count), {:controller => 'news', :action => 'index', :project_id => membership.project.identifier} %></span>) </span> --></td>
-						</tr>
-						<tr>
-							<td colspan="2" width="580" >
-							<p class="font_description">
-								<%= membership.project.description%>
-							</p></td>
-						</tr>
-						<tr>
-							<td align="left"><span class="font_lighter"> <%= format_time(membership.created_on) %></span></td><!-- modified by ming -->
-							<td  align="right" > 
-								
-							<% if membership.roles.sort.collect(&:to_s).join(', ') =='Manager' %>
-							Teacher
-							<% elsif membership.roles.sort.collect(&:to_s).join(', ') =='Reporter' %>
-							Student
-							<% elsif membership.roles.sort.collect(&:to_s).join(', ') =='TA' %>
-							TA
-							<% end %>
-						    </td>
-						</tr>
-					</table></td>
-				</tr>
-
-			</table>
-
-		</li>
-		<% end %>
-	</ul>
-	
-	<% end %>
-	<%= call_hook :view_account_left_bottom, :user => @user %>
-</div>
diff --git a/files/delete.me b/files/delete.me
deleted file mode 100644
index 18beddaa8..000000000
--- a/files/delete.me
+++ /dev/null
@@ -1 +0,0 @@
-default directory for uploaded files
\ No newline at end of file