After I installed freepbx 2.5.1, all module in web interface were gone after reboot the server

FreePBX Installation / Upgrade
1

after I installed freepbx 2.5.1, all module in web interface were gone after reboot the server. I use asterisk 1.6.0.1, CentOS 5.2 and freepbx 2.5.1

Please help me to solve it…