Thanks Stuart!
I commented out the rewrite mode of lighttpd (url.rewrite-once) and I have access to the page! 🙂
on the other hand, if I can abuse your kindness, I have this error now:
ParseError: syntax error, unexpected 'topics' (T_STRING), expecting '{' (0)
#0 /usr/home/xxx/system/Application/Application.php(165): IPS\_Application::constructFromData()
#1 /usr/home/xxx/applications/core/modules/setup/upgrade/login.php(81): IPS\_Application::applications()
#2 /usr/home/xxx/system/Dispatcher/Controller.php(101): IPS\core\modules\setup\upgrade\_login->manage()
#3 /usr/home/xxx/system/Dispatcher/Setup.php(220): IPS\Dispatcher\_Controller->execute()
#4 /usr/home/xxx/admin/upgrade/index.php(34): IPS\Dispatcher\_Setup->run()
#5 {main}
#0 /usr/home/xxx/init.php(908): IPS\_Log::log()
#1 [internal function]: IPS\IPS::exceptionHandler()
#2 {main}
Thank you