White (blank) page after login

Hi,

After login our journal site, I see a blank page without any things!
(journal site/index.php/index/user) page

I can not manage or change any things

I used OJS 2.4.6 version, I upgraded it to 2.4.8, but the problem exist

Please help me to fix the problem

Follow the instructions here, and report the particular error message(s), if not self-evident.