Hi @milach,
Do you see other warnings/error messages like these ones…
Warning: Cannot modify header information - headers already sent by (output started at /home/dpgpsifp/psicodebate.dpgpsifpm.com.br/lib/pkp/classes/security/Validation.inc.php:58) in /home/dpgpsifp/psicodebate.dpgpsifpm.com.br/lib/pkp/classes/session/SessionManager.inc.php on line 225
…described on this thread?
Regards,
Alec Smecher
Public Knowledge Project Team