Error message

Warning: Cannot modify header information - headers already sent by (output started at /mnt/home/visuafus/public_html/bahusa.net/includes/common.inc:2861) in drupal_send_headers() (line 1551 of /mnt/home/visuafus/public_html/bahusa.net/includes/bootstrap.inc).
Error: Call to undefined function mail() in DefaultMailSystem->mail() (line 79 of /mnt/home/visuafus/public_html/bahusa.net/modules/system/system.mail.inc).

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