Prestashop 1.7 PHP fatal error - urgent help

[Anubis2702]

Hello, I was translating a module and at some point stopped receiving "succesfully saved" notification about the translations. Then I refreshed the page and got HTTP 500 Error and the BO not working anymore.

AH01071: Got error 'PHP message: PHP Fatal error: Cannot declare interface Symfony\\Component\\DependencyInjection\\ContainerAwareInterface, because the name is already in use in /var/www/vhosts/ladies-tailor.ro/httpdocs/app/cache/prod/classes.php on line 7247\n'

The FO is working.

[des2006]

I encountered similar situation several times.  Have to re-install PS to solve problem.  Also maybe some addons not compatible with PS 1.7.  Should install default PS modules and test well before adding other addons.

[Anubis2702]

Reinstalling PS is not an option.

I removed this function:

interface ContainerAwareInterface{public function setContainer(ContainerInterface $container = null);}

from .../prod/classes.php and now the backoffice is working.

What is this function for, what should I expect to not work anymore? 

Edited January 26, 2017 by Anubis2702 (see edit history)

[amerigeau]

Hello, here is the solution : https://www.arnaud-merigeau.fr/prestashop-1-7-resolu-cannot-redeclare-class-containerawareinterface/