"Access Denied" error, or user is repeatedly prompted for credentials when trying to connect to Office 365 by using a rich client application

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Article ID: 2630976 - View products that this article applies to.
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When users try to access a Microsoft Office 365 resource from a rich client application such as Microsoft Outlook or Microsoft Lync, one of the following symptoms occurs:
  • Users are repeatedly prompted to enter their credentials.
  • Users receive the following error message:
    Access Denied


To fix this problem, reset the user's password. To do this, follow these steps:
  1. Open a web browser, browse to the Office 365 portal (https://portal.microsoftonline.com), and then sign in by using the user's expired credentials.
  2. When you're prompted, enter a new Office 365 password for the user. Make sure that the password meets the criteria for Office 365.


This problem occurs if a user's password has expired in Office 365. When a user's password expires, access to Office 365 resources is immediately limited. For rich client authentication, the change in access occurs without a detailed explanation. This is because rich client applications can't notify users when their passwords expire or provide password reset functionality.

In Office 365, you can also enable password expiry notification by installing the latest version of the Microsoft Online Services Sign In Assistant. To do this, follow these steps.
  1. Sign in to the Office 365 portal (https://portal.microsoftonline.com) by using the user's new password.
  2. On the Home page, do the following:
    1. In the pane on the right, click Downloads.
    2. Under Set up and configure your Office desktop apps, click Set up .
    Note After you complete this step, the Office 365 Desktop Setup Tool runs again. This updates the Microsoft Online Services Sign In Assistant installation package on the client computer. The updated package enables password expiry notifications and password resets.

    The updated package for the Microsoft Online Services Sign In Assistant can also be manually downloaded from the following Microsoft website:
About the Microsoft Online Services Sign In Assistant

The following features are introduced in version 7.250.4287.0 of the Microsoft Online Services Sign In Assistant package:
  • Password expiry notification

    For users of Office 365 rich client applications (except for Microsoft Outlook), a notification balloon is displayed on users' desktops 14 days before the 90-day password expiration time-out to let users know that they have to change their password. Users are prompted every day after that until they change their password.

    Every time that authentication is made through the Sign In Assistant's authentication stack, the Sign In Assistant uses the credentials that are supplied by the user to examine the password expiry status for that user account.

    Note Because Outlook connections authenticate without the Sign In Assistant, the Outlook connection doesn't trigger the Sign In Assistant to examine password expiry status.
  • Password reset

    When the notification balloon is displayed within the 14-day period, users can perform one of the following actions:
    • Ignore the notification. (The balloon is no longer displayed on the desktop after five seconds pass.)
    • Click X to close the window.
    • Click the balloon to change the password. Users are then redirected to the Office 365 portal to change their password.


For information about related issues, go to the following Microsoft Knowledge Base articles:
  • 2637629 How to troubleshoot computer issues that limit Office 365 rich client authentication
  • 2461628 A federated user is repeatedly prompted for credentials during sign-in to Office 365, Windows Azure, or Windows Intune
Still need help? Go to the Office 365 Community website.


Article ID: 2630976 - Last Review: February 25, 2014 - Revision: 24.0
Applies to
  • Microsoft Office 365 for enterprises (pre-upgrade)
  • Microsoft Office 365 for small businesses  (pre-upgrade)
  • Microsoft Office 365 for education  (pre-upgrade)
  • Microsoft Office 365
o365 o365e o365p o365022013 after upgrade o365062011 pre-upgrade o365m o365a KB2630976

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