Blank login page after installation in Linux environment

[nptest]

I searched through forum and mantis but cannot find the answer that solve my issue. Some kind soul please reply me on this:

Have installed testlink 170 into my Linux environment. When I go to login page, it is showing blank page. I have set the file permissions to 777 (have all access rights). Please give me some lights on how to solve this. I'm new in using Linux. Thanks!