Microsoft 365: Outlook and mobile device connectivity troubleshooting resources

Introduction

This article contains links to technical resources and support information for troubleshooting Microsoft Outlook connectivity and mobile device connectivity in Microsoft 365.

Cannot connect to Exchange Online by using Outlook

Help articles

Poor performance

Knowledge Base articles

  • 2413813 How to troubleshoot issues in which Outlook 2007 or Outlook 2010 crashes or stops responding (hangs) when it's used with Microsoft 365
  • 2441551 Outlook performance is slow in the Microsoft 365 environment
  • 2646504 How to remove automappping for a shared mailbox in Microsoft 365

Auto Account Setup fails in Microsoft 365

Knowledge Base articles

  • 2404385 Outlook can't set up a new profile by using Exchange Autodiscover for an Exchange Online mailbox in Microsoft 365
  • 2427141 You can't find a user in the offline address book in Microsoft 365
  • 2429946 How to troubleshoot the Outlook Offline Address Book in a Microsoft 365 environment
  • Anonymous Authentication Enabled for Virtual Directory
  • 2710606 Error message in the Exchange Remote Connectivity Analyzer tool when you test the Outlook Anywhere feature in a Microsoft 365 environment: "Mutual Authentication could not be established"

Repeated password prompts in Outlook

Knowledge Base articles

  • 2466333 Federated users can't connect to an Exchange Online mailbox
  • 2637629 How to troubleshoot non-browser apps that can't sign in to Microsoft 365, Azure, or Intune

Cannot view free/busy information in the Outlook calendar

Knowledge Base articles

  • 2555008 How to troubleshoot free/busy issues in a hybrid deployment of on-premises Exchange Server and Exchange Online in Microsoft 365
  • 2581088 How to troubleshoot issues that prevent a user from viewing other users' free/busy information in Office Outlook 2007 and in Outlook 2010 in a Microsoft 365 environment

Cannot configure mobile devices

Knowledge Base articles

  • 2427193 A mobile device can't connect to Exchange Online by using Exchange ActiveSync
  • 2679626 Your Microsoft 365 email account is not automatically set up on your Google Android device or on your Apple iOS-based device through the Autodiscover service

Tools and Diagnostics wiki articles in the Microsoft 365 Community

The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.

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