Please help me. No output at all.

[eluser]Unknown[/eluser]
It works well in my own environment. Bug when I copy the whole project to another server, No output at all. And No error message at all, although I have turned on the error reporting.

I doubt this server is ok. so I add some code with wrong format in index.php, it will output an error message. and if I remove those lines, Nothing output again.

that environment is:
apache
php 5.3.2
apache Apache/2.2.15 (Unix)

please help me.