Mail sidebar

The Mail sidebar lists mailboxes, folders, and flagged items for the email accounts you use in Mail. If the sidebar isn’t shown, choose View > Show Sidebar, or press Control-Command-S. If an expected email account isn’t listed in the sidebar, choose Mail > Settings, click Accounts, click Account Information, then make sure the account is enabled.

To increase the size of icons and text in the Mail sidebar, choose Apple menu > System Settings, then click Appearance in the sidebar. (You may need to scroll down.) On the right, click the pop-up menu next to “Sidebar icon size,” then choose a size.