==== 必填信息。没有填写将不予回复 ====
- iRedMail 版本号：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：RED HAT 6.3
- 与您的问题相关的日志信息：
Oct 11 10:28:06 imap-login: Info: Login: user=<nietuo@verif.phytium.com>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, mpid=4474, secured, session=<imuGLDxbtgB/AAAB>
Oct 11 10:28:06 imap(nietuo@verif.phytium.com): Error: chdir(/var/vmail/vmail1/verif.phytium.com/n/i/e/nietuo-2017.10.10.15.45.50//) failed: Permission denied (euid=2000(vmail) egid=2000(vmail) missing +x perm: /var/vmail/vmail1, dir owned by 0:0 mode=0700)
Oct 11 10:28:06 imap(nietuo@verif.phytium.com): Error: chdir(/var/vmail/vmail1/verif.phytium.com/n/i/e/nietuo-2017.10.10.15.45.50/) failed: Permission denied
Oct 11 10:28:06 imap(nietuo@verif.phytium.com): Error: user nietuo@verif.phytium.com: Initialization failed: Namespace '': stat(/var/vmail/vmail1/verif.phytium.com/n/i/e/nietuo-2017.10.10.15.45.50//Maildir) failed: Permission denied (euid=2000(vmail) egid=2000(vmail) missing +x perm: /var/vmail/vmail1, dir owned by 0:0 mode=0700)
Oct 11 10:28:06 imap(nietuo@verif.phytium.com): Error: Invalid user settings. Refer to server log for more information.
====

具体做法：
(1)备份：执行/var/vmail/backup/backupmysql.sh；拷贝生成的各个sql.bz2；拷贝/var/vmail/vmail1文件夹
(2)恢复：在另一台服务器上安装iredmail；进入mysql数据库，删除与iredmail相关的amavisd等6个数据库；导入备份过来的sql；将新iredmail的/var/vmail/vmail1替换掉备份过来的文件夹。
(3)邮箱登陆报错：连接至IMAP服务器失败。