ragazzi ho un problema...

in locale è tutto ok, su server in tutte le pagine dove sta il session_start() mi da

Warning: session_start(): Cannot send session cookie - headers already sent by (output started at /home/alexuc/public_html/alexuc/sistemitaly/control.php:2) in /home/alexuc/public_html/alexuc/sistemitaly/control.php on line 12

Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /home/alexuc/public_html/alexuc/sistemitaly/control.php:2) in /home/alexuc/public_html/alexuc/sistemitaly/control.php on line 12

e non funziona la sessione...