Article ID: 2277579 - View products that this article applies to.
Not sure what release of Office 365 you're using? Go to the following Microsoft website:
Am I using Office 365 after the service upgrade?
When you use an email program other than Microsoft Outlook or Microsoft Outlook Web App to try to connect to a mailbox that's hosted in Microsoft Office 365, you can't connect to the mailbox.
Install an email program that's supported for accessing mailboxes in Office 365.
This behavior is by design. Currently, only certain versions of Microsoft Outlook and of Microsoft Entourage for Mac are supported to access mailboxes that are hosted in Office 365.
For more information about the system requirements for Office 365, go to the following Microsoft websites:
Still need help? Go to the Office 365 Community
Article ID: 2277579 - Last Review: August 20, 2013 - Revision: 30.0