如果您使用的是G Suite，则必须与G Suite管理员联系，以在Google管理面板中启用对用户应用的不安全访问，URL如https://admin.google.com/{YOUR_DOMAIN_NAME}/AdminHome?hl=en#ServiceSettings/notab=1&service=securitysetting&subtab=lesssecureappsaccess

If you are using G Suite, you have to contact your G Suite administrator to enable not secure access for users apps in Google Admin panel, URL like https://admin.google.com/{YOUR_DOMAIN_NAME}/AdminHome?hl=en#ServiceSettings/notab=1&service=securitysetting&subtab=lesssecureappsaccess

或采用这种方式(对于G Suite管理员)

or go this way (for G Suite admin)

1. https://admin.google.com
2. 安全设置
3. 基本设置(第一个链接)
4. 安全性较低的应用程序->转到安全性较低的应用程序的设置
5. 强制所有用户访问安全性较低的应用程序(不推荐)
6. 保存
7. 利润(可以在1-2分钟内生效，请等待一段时间)

1. https://admin.google.com
2. Security settings
3. Basic settings (first link)
4. Less secure apps -> Go to settings for less secure apps
5. Enforce access to less secure apps for all users (Not Recommended)
6. Save
7. PROFIT (can take effect in 1-2 mins, wait for some time please)