Configuring proinbox.com for an iPhone

What is proinbox.com:

Fastmail is an email hosting company based in Melbourne, Australia. In addition to its Fastmail-branded services, the company also operates Topicbox, a mailing list service, and Pobox, an email service it acquired in 2015. The company was acquired by Opera Software in 2010 but became independent again in 2013 through a staff buyout. Its servers are located in Bridgewater, New Jersey and Seattle, Washington. Source: https://en.wikipedia.org/wiki/Fastmail

Configuring proinbox.com:

It is possible that Mail will find the e-mail parameters itself, and complete setting up your account. Follow the following steps first in order to see if it will:

1. Go to Settings > Mail then tap Accounts
2. Click Add Account > Other, and tap Add Mail Account
3. Enter your name (can be any name), your email address, password then a description for account.
4. Click Next. The Mail app should now try and find the mail parameters and finish setting your account. If Mail finds your e-mail parameter, click Done to complete your setup.

In case the Mail app can't find your email configuration, it means that you will have to enter them yourself. I think you may find the following information useful:

Incoming Mail Server (IMAP) Settings

Outgoing Mail Server Settings

Tap Next, then follow these steps:

1. Select IMAP or POP for your new account. If you are not certain which one to choose, contact proinbox.com.
2. Type the required information (You will want to have a look at the table above) for Incoming Mail Server and Outgoing Mail Server. Then click Next.
3. If your mail settings are correct, click Save to complete the setup. If your mail settings are incorrect, you will be asked to modify the configuration.
4. If you still can't set up the account or save the settings, contact the e-mail provider.