我的postfix配置有问题。我的服务器在Debian 8上运行。我在这里安装了nginx。 PHP版本：5.6（PHP5-FPM服务）
我已经通过命令安装了postfix和mailutils：
apt-get install postfix
apt-get install mailutils
phpinfo（）返回：
sendmail_from test@bociuch.pl
sendmail_path /usr/sbin/sendmail -t -i
SMTP localhost
smtp_port 25
简单的PHP脚本：
mail('test@email.com', 'test', 'test');
邮件功能返回true但电子邮件不会发送给其他人。
这个问题可能是什么原因？有人有过这种问题吗？我应该在哪里找到错误？提前谢谢！
最近的日志（/var/log/mail.log）：
Apr 18 13:50:20 bociuch sendmail[12748]: u3IHoKfU012748: to=dominikg@infobuzer.pl, ctladdr=www-data (33/33), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=30095, relay=[127.0.0.1] [127.0.0.1], dsn=2.0.0, stat=Sent (u3IHoKbp012749 Message accepted for delivery)
Apr 18 13:50:20 bociuch sm-mta[12751]: STARTTLS=client, relay=infobuzer.nazwa.pl., version=TLSv1/SSLv3, verify=FAIL, cipher=ECDHE-RSA-AES256-GCM-SHA384, bits=256/256
Apr 18 13:50:20 bociuch sm-mta[12751]: u3IHoKbp012749: to=<dominikg@infobuzer.pl>, ctladdr=<www-data@bociuch.pl> (33/33), delay=00:00:00, xdelay=00:00:00, mailer=esmtp, pri=120349, relay=infobuzer.nazwa.pl. [85.128.177.26], dsn=5.7.1, stat=User unknown
Apr 18 13:50:21 bociuch sm-mta[12751]: u3IHoKbp012749: u3IHoLbp012751: DSN: User unknown
Apr 18 13:50:22 bociuch sm-mta[12751]: u3IHoLbp012751: to=<www-data@bociuch.pl>, delay=00:00:01, xdelay=00:00:00, mailer=local, pri=30000, dsn=2.0.0, stat=Sent
Apr 18 14:05:14 bociuch postfix/master[13234]: fatal: bind 0.0.0.0 port 25: Address already in use
Apr 18 14:05:32 bociuch postfix/postdrop[13249]: warning: unable to look up public/pickup: No such file or directory
Apr 18 14:28:40 bociuch postfix/postdrop[13368]: warning: unable to look up public/pickup: No such file or directory
Apr 18 14:29:01 bociuch postfix/postdrop[13371]: warning: unable to look up public/pickup: No such file or directory
Apr 18 15:03:32 bociuch postfix/postdrop[13677]: warning: unable to look up public/pickup: No such file or directory