Service Desk

Information Technology Services

Office 365 Login Error

If you are experiencing an error logging into the Outlook desktop client or other Microsoft application such as Word, the following information will help you resolve the issue.

Why is the Error Occurring?

Cal Poly has assigned an Office 365 account to you.  This account is the email address that you use to sign into your Cal Poly Office 365 account.

A Microsoft personal account is the one that you use for services such as Xbox Live,, Windows 8 or 10, or Windows Phone.

The Cal Poly account and the Microsoft personal account are two different accounts.

If you setup your Microsoft personal account and associated your Cal Poly username with the personal account, when you attempt to login to Outlook or other Microsoft desktop applications, Microsoft detects that your Cal Poly username is associated with both your Cal Poly account and your personal account and displays the screenshot below.

If you attempt to login using the Work or School account option, your will be presented with the Cal Poly Portal login page but your username and password won't authenticate and you'll receive an error.

To resolve the issue, you will need to click on the link Rename your personal Microsoft account and login to your personal Microsoft account.

Office 365 Duplicate Account

The Solution

On the Rename your personal account page, scroll down the page until you see the "Your info page" link.  Click on that link.

Rename Office 365 Personal Account

After logging into your personal Microsoft account,

  1. Click on the option Manage your sign-in email or phone number
Office 365 Personal Account Settings
  1. Your Cal Poly account will be displayed as the primary alias.  Click on the Add email link.

Office 365 Account Alias Configuration

  1. You will need to do one of the following:
  • Create a new email address, or
  • Associate your Microsoft personal account with a different email address, such as Gmail.

    Adding an Alias

    1. After adding another email address, you will need to make the new address the Primary alias.  Click on the link Make primary.

    List of Account Aliases

    1. Once you have associated your Microsoft personal account with another email address, you will need to remove the Cal Poly username as an Account Alias.

    Removing Cal Poly Address from Account Alias

    1. You will receive a message about removing your Cal Poly username from your Microsoft personal account. Click Remove.

    Alias Account Removal Confirmation
    After you have completed these steps, you will not receive the Microsoft dialog box asking you to select which account to login to.

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