How to log in to multiple accounts/switch accounts?

PC_Mail:

You can log in/switch multiple accounts at the same time, and add account configurations through [New Mailbox] under the account on the left column.

PC_IM：

PC_IM can log in to multiple accounts at the same time, reopen the application, and enter the account and password.

Mobile:

Via [Me] > [Settings] > [Switch Account] to select the account you want to switch or add a new account.