This guide is based on a Lumia 630 Windows Phone (running Windows Phone 8.1). Every Windows device will have a slightly different process. In addition you may choose to setup email with an App of your own choosing, rather than the one built into your device. If you need assistance with a specific device or app please contact your vendor, or Topmail Support. If you only need the server settings information for Topmail you can get that here: Topmail Server Settings.
Open your settings. Scroll down to the "email+accounts" and tap on it.
Tap on "add an account"
Scroll down and tap on "other account (POP and IMAP)"
Enter your full @topmail email address and your passphrase (password).
Tap on "sign in"
If "sign in" fails, tap on "try again"
Tap on "advanced"
Tap on "Internet email" as the account type
Enter the following settings:
Enter account name (eg. "Topmail")
Enter your name (eg. Your Name)
Incoming email server: imap.topmail.com
Account type: IMAP4
Scroll down
Continue to enter settings:
User name: your full @topmail.com email address
Password: your @topmail passphrase (password)
Outgoing (SMTP) email server: smtp.topmail.com
Scroll down
Tap on "advanced settings"
Check the box indicated for:
Outgoing server requires authentication
Use the same user name and password for sending email
Require SSl for incoming mail
Require SSL for outgoing mail
Scroll down
Select your notification and sync preferences.
Tap on "sign in"