Setting up macOS Mail - Catalina, Big Sur, Monterey & Ventura

In this guide, we will set up our one.com email account in the Mail application running macOS 10.15 - Catalina, macOS 11 - Big Sur,  macOS 12 - Monterey or macOS 13 - Ventura.

• Step 1 - Add new account
• Step 2 - Account Settings
• Step 3 - Mail Server settings
• Step 4 - Select apps to use
• Step 5 - Setup email synchronisation
• Step 6 - You are done!

Step 1 - Add new account

Open the Mail application via your Dock or in the Applications folder in Finder. If you don't have any existing email accounts set up in the Mail application, the New account setup window will open up automatically. In that case, select Other Email Account and continue to Step 2.

1. Click on Mail in the top bar
2. Select Preferences in the menu
3. In the preferences window, click the Accounts tab if it's not selected automatically.
4. On the left side, you will see a list of all the existing email accounts in the Mail application. Click the small + icon in the bottom left corner of the list.

This will open up the New account setup window.

Step 2 - Account Settings

In the New account setup window, enter the following:

1. Name: The display name to show for the email account.
2. Email Address: The email address you want to add.
3. Password: The email account's password.
4. Click Sign In.

Step 3 - Mail server settings

The Mail application will attempt to verify your details but fail after a few moments, showing you an error message "Unable to verify account name and password". This is normal and will not hinder you from continuing your setup.

Enter the following information:

1. Email Address: Your email address.
2. Username: Your email address.
3. Password: Your email account password. (If not already filled in)
4. Account Type: IMAP
5. Incoming Mail Server: imap.one.com
6. Outgoing Mail Server: send.one.com

Click Sign In.

Note: Weren’t you able to log in - Despite using the settings from above? Please check if you can log into Webmail. If you don't remember your email password, read our guide on how to change your mail password.

Step 4 - Select apps to use

Next, you will be asked to Select the apps you want to use with this account. Here, ensure you only have selected Mail.

Click Done.

Step 5 - Setup email synchronisation

At this point, the Mail application will start downloading your emails and folders from our servers. Before we begin using the Mail application, setting up your email synchronisation is important to prevent emails from getting lost or moved to the wrong folder. This is particularly important if you wish to access the same email account on multiple devices, e.g. your computer and mobile devices.

By default, the Mail application will synchronise your Inbox, Drafts and custom folders automatically, but Sent, Spam and Trash folders will not be synchronised correctly.

To correct this, we need to go in and adjust some of our settings for our email account in the Mail application:

1. Click on Mail in the menu at the top of the screen and select Preferences.
2. In the Preferences window, click the Accounts tab.
3. Select your email account in the left-hand menu.
4. Once selected, click the Server Settings tab on the right-hand side of the window.
5. Click the Advanced IMAP Settings button.
6. In the small window that opens up, ensure that the IMAP Path Prefix is set to INBOX (in capital letters).
7. Click OK to close the window.

Finally, In the Preferences window, click the Mailbox Behaviours tab and ensure you have the following setup:

• Drafts Mailbox is set to INBOX/Drafts
• Sent Mailbox is set to INBOX/Sent
• Junk Mailbox is set to INBOX/Spam
• Trash Mailbox is set to INBOX/Trash

Once you select the folder, the Mail application will connect it and change the name by appending INBOX/ to it.

Note: Empty folders will not show up in the drop-down menu. If this is a brand new email account, log in to your email account via the one.com Webmail and place a draft email in the Drafts, Sent, Spam and Trash folders. This will allow the Mail application to see them and for you to select them in the drop-down menus.

Step 6 - You are done!

You did it! You can now use your one.com email account with the Mac Mail application!

Related articles:

• How can I backup my emails in Outlook, Thunderbird or Apple Mail?
• How do I change my email password?