Non default installed modules doesn't work on Front Office - 500 Internal server error

[benjamim]

Hi there!

I've installed PrestaShop v.1.4.1.0 and it works fine! Then I installed some modules that aren't installed by default (ie: Paypal module, Whislist module, Loyalty points module, etc). The installation seems to be OK, but when I try to use it (on Front Office, as a customer), they thow a '500 Internal Server Error':

"Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, [email protected] and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request."

This happens with each module I've installed...why? I've already seen the several modules configurations and they are fine. What can be my problem?

By the way, where can I find the error log of front office? On the server, above admin folder there is a error_log file but it seems to be from BackOffice, not from FrontOffice. It doesn't show any error about my problem.

Can someone help me please? Any idea what the problem can be?

Thanks.

Regards,
Benjamim