The problem is solved

It seems I need to have all the portal files for all styles installed, otherwise it will give an error

Cheers from Lisbon

Your Portal Version: 2.0.0
Your phpBB Type: Standard phpBB3
MODs installed: No
Your knowledge: Beginner
Boardlink: http://forumdematematica.org/

MySQL Version: 5.5.23-55

What have you done before the problem was there?
I installed the portal

What have you already tryed to solve the ...