通过138企业邮箱网页端 138.gz.cn 登录邮箱的密码无法设置在第三方客户端（如foxmail,outlook等），或者手机端（手机邮件收发APP）上面，必须生成客户端专属密码方能设置成功。
The password for logging into the email through the 138.gz.cn enterprise email website cannot be set on third-party clients (such as Foxmail, Outlook, etc.) or mobile apps (such as mobile email sending and receiving apps). A client specific password must be generated to successfully set it.

1. 打开设置-邮件-账户-添加账户
Open Settings - Email - Account - Add Account

2. 添加账户, 选择“其他”账户,添加邮件账户,输入邮箱帐号，客户端专用密码，下一步
Add account, select "Other" account, add email account, enter email account, client specific password, next step

3. 进入新账户配置页面，建议选择IMAP（查看IMAP和POP不同）,
输入收件（IMAP）服务器地址：c2.icoremail.net、完整的邮箱地址、客户端专用密码（查看生成教程）、端口：993、安全类型选择SSL/TLS

输入发件（SMTP）服务器地址：c2.icoremail.net、完整的邮箱地址、客户端专用密码（查看生成教程）、端口：465、安全类型选择SSL/TLS
如果选择POP协议，输入收件（POP）服务器地址：c2.icoremail.net、完整的邮箱地址、客户端专用密码（查看生成教程）、端口：995、安全类型选择SSL/TLS
即可配置成功。

On the new account configuration page, it is recommended to choose IMAP (to see if IMAP and POP are different),

Enter the recipient (IMAP) server address: c2.icoremail.net、 Complete email address, client specific password (see generation tutorial), port: 993, security type selection SSL/TLS

Enter the sender (SMTP) server address: c2.icoremail.net、 Complete email address, client specific password (see generation tutorial), port: 465, security type selection SSL/TLS

If you choose the POP protocol, enter the recipient (POP) server address: c2.icoremail.net、 Complete email address, client specific password (see generation tutorial), port: 995, security type selection SSL/TLS

The configuration can be completed successfully.