Name: Your Name (Whatever you want)
Email: xxxx@bestmail.us
Password: Your bestmail.us account password
Description: bestmail.us
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Hostname: imap.fastmail.com
Username: xxxx@bestmail.us
Password: Your bestmail.us account password
Hostname: smtp.fastmail.com
Username: xxxx@bestmail.us
Password: Your bestmail.us account password
Click Save Button
Use SSL: Yes
Authentication: Password
Server Port: 993
Use SSL: Yes
Authentication: Password
Server Port: 587