==== 必填信息。没有填写将不予回复 ====
- iRedMail 版本号：iRedMail-0.9.2
- 使用哪个数据库存储用户帐号（OpenLDAP，MySQL，PostgreSQL）：Mysql
- 使用的 Linux/BSD 发行版名称及版本号：CentOS release 6.7 (Final)
- 与您的问题相关的日志信息：
====

安装iRedMail出现的错误：

[ INFO ] Create self-signed SSL certification files (2048 bits).
[ INFO ] Generate a strong, unique Diffie Hellman Group with openssl, please wait.
[ INFO ] Create required system account: vmail, iredadmin, iredapd.
[ INFO ] Configure Nginx web server and uWSGI.
[ INFO ] Configure PHP.
[ INFO ] Configure MySQL database server.
[ INFO ] Setup daily cron job to backup SQL databases: /var/vmail/backup/backup_mysql.sh
[ INFO ] Configure Postfix (Message Transfer Agent).
[ INFO ] Configure Cluebringer (postfix policy server).
[ INFO ] Configure Dovecot (pop3/imap/managesieve server).
[ INFO ] Configure ClamAV (anti-virus toolkit).
usermod: user 'amavis' does not exist
chmod: cannot access `/var/spool/amavisd/tmp': No such file or directory
chmod: cannot access `/var/spool/amavisd/quarantine': No such file or directory
[ INFO ] Configure Amavisd-new (interface between MTA and content checkers).
chgrp: invalid group: `amavis'
chmod: cannot access `/etc/amavisd/amavisd.conf': No such file or directory
chmod: cannot access `/etc/amavisd/amavisd.conf': No such file or directory
Can't open /etc/amavisd/amavisd.conf: No such file or directory.
Can't open /etc/amavisd/amavisd.conf: No such file or directory.
Can't open /etc/amavisd/amavisd.conf: No such file or directory.
Can't open /etc/amavisd/amavisd.conf: No such file or directory.
Can't open /etc/amavisd/amavisd.conf: No such file or directory.
Can't open /etc/amavisd/amavisd.conf: No such file or directory.
sed: can't read /etc/amavisd/amavisd.conf: No such file or directory
/apps/soft/iRedMail-0.9.2/functions/amavisd.sh: line 151: /etc/amavisd/amavisd.conf: No such file or directory
Can't open /etc/amavisd/amavisd.conf: No such file or directory.
/apps/soft/iRedMail-0.9.2/functions/amavisd.sh: line 159: /etc/amavisd/amavisd.conf: No such file or directory
Can't open /etc/amavisd/amavisd.conf: No such file or directory.
Can't open /etc/amavisd/amavisd.conf: No such file or directory.
Can't open /etc/amavisd/amavisd.conf: No such file or directory.
Can't open /etc/amavisd/amavisd.conf: No such file or directory.
/apps/soft/iRedMail-0.9.2/functions/amavisd.sh: line 265: /etc/amavisd/amavisd.conf: No such file or directory
chown: invalid user: `amavis:amavis'
chown: invalid user: `amavis:amavis'
/apps/soft/iRedMail-0.9.2/functions/amavisd.sh: line 38: /etc/amavisd/amavisd.conf: No such file or directory
Can't open /etc/amavisd/amavisd.conf: No such file or directory.
Can't open /etc/amavisd/amavisd.conf: No such file or directory.
/apps/soft/iRedMail-0.9.2/functions/amavisd.sh: line 424: /etc/amavisd/amavisd.conf: No such file or directory
/apps/soft/iRedMail-0.9.2/functions/amavisd.sh: line 463: /etc/amavisd/amavisd.conf: No such file or directory
Can't open /usr/sbin/amavisd: No such file or directory.
/apps/soft/iRedMail-0.9.2/functions/amavisd.sh: line 488: /etc/amavisd/amavisd.conf: No such file or directory
/apps/soft/iRedMail-0.9.2/functions/amavisd.sh: line 507: /etc/amavisd/amavisd.conf: No such file or directory
/apps/soft/iRedMail-0.9.2/functions/amavisd.sh: line 536: /etc/amavisd/amavisd.conf: No such file or directory
/apps/soft/iRedMail-0.9.2/functions/amavisd.sh: line 541: /etc/amavisd/amavisd.conf: No such file or directory
[ INFO ] Configure SpamAssassin (content-based spam filter).

请问如何解决？