I have same problem (Strict Standards: Declaration of JParameter::loadSetupFile() should be compatible with JRegistry::loadSetupFile() in)

I dont have cpanel.php file in modals
K2 v2.6.7
joomla 2.5.18

Thanks for any help/tip/advise

@landalf this is just a warning and not an actual error. Just Disable error reporting from your global configuration.