If you are using Microsoft Outlook as your email client, you should use the default Exchange connection type. Exchange also provides direct access to the USC calendar that is a part of your Office 365 account.
Exchange only requires that you provide your email address and password for set up IMAP, however, requires additional server information. There are several advantages to setting up your email client to use Exchange rather than IMAP settings.
You can set your email client to access your Office 365 account using either Exchange or Internet Message Access Protocol (IMAP) settings. This page provides links to documentation on how to configure your email client to access Office 365. ITS highly recommends using the Outlook email client or Outlook Web App (OWA) to access your USC Office 365 email.