[Typo3-linux] URGENT!I am receiving 500 Server error in editing pages in Administration panel

[Uros Nedic]

I downloaded and installed on my Linux server typo3_src-3.8.0 and
testsite-3.7.0. After sucessfull instalation I entered into typo3
Administration panel. When I enter into Web -> Page I cannot see the page
and I receive 500 Server error. Also when I enter into Web -> View I can see
the page but I cannot edit by clicking on icons on the preview page.

Anyone can help?
Thanks,
Uros