module not exists: xxxx Error in ThinkPHP

Introduction

ThinkPHP is a very charming PHP framework to easily build a website. It's structured in MVC(Module, View, Controller) and provides convenient module to access to database and support RESTful request.

My Problem

I've deployed my project in Windows 10 for a long time and recently I need to deploy it to Ubuntu 16.04 Server. Then I just copied all the files to the new place in Ubuntu, and visited the website. Nothing was displayed. A BLANK page. I don't know what's wrong with this.

Hypothesis and Solution

1. I thought maybe the permission is wrong. So I changed the permission to allow full access.

chmod -R 0777 tp5/

Didn't work

1. If the default module works ？
   
   then I visited http://xxxxxx.xxx.xxx.xxx/tp5/, which actually is http://xxxxxx.xxx.xxx.xxx/tp5/index/index/access in my case. I change the default_action to access in config.php
   
   It worked

2. Then an idea occurred to me that Windows is case-insensitive, while Linux is not. I typed publication in the URL but the folder actually is Publication. But it's useless to change it to the Titled form in URL.
   
   LOL
   
   Finally, I changed the folder to lower-case. Waaaaah, it worked.