Here is the step by step procedure required to correct this problem.

1) log in to your Cpanel
2) Scroll down to the file manager section and click on the "File Manager" icon.
3) Click on the "radio buton" next to "Web Root" (public html/www)
4) Place a "checkmark" in the little box next to "Show Hidden Files".
5) Next click the "GO" button to enter the File Manager.

i CANNOT exactly see any box next to show hidden files. please let me see some screenshots. im installing phbb in root directory. Thanks.