If you're still using Outlook Express for checking your Windows Live Hotmail, listen up. Microsoft will be cutting off your access in three months. On September 1, 2009, the support for Distributed Authoring and Versioning (WebDAV), the protocol that Outlook Express and a handful of older clients currently use to access Hotmail, will be discontinued.
As Neowin reported in April of last year, Microsoft originally planned to cut off access for Outlook Express users on June 30, 2008. However the WebDAV protocol got a stay of execution after users complained that it was too soon. Microsoft's management agreed and gave users another year to make the migration. Microsoft has stated that these changes are necessary to support the larger and larger mailbox sizes that Hotmail supports. The say that that due to WebDAV's age, it can no longer keep up with the demands placed on it.
Outlook Express was last included with Windows XP. Windows Vista includes Windows Mail, but it does not feature the direct Hotmail connection features that were present in Outlook Express. Windows Vista users who wish to connect to their Hotmail accounts can use Windows Live Mail, which uses Microsoft's new favored protocol, DeltaSync. Users of Outlook Express who wish to continue using the client can reconfigure the client to connect using POP3, which was added to Hotmail in March 2009.
As part of Microsoft's new distribution strategy, Windows 7 does not include any mail client by default, but users can optionally install Windows Live Mail.
This change will have no affect on users of Microsoft Outlook 2003/2007 using the Office Outlook Connector since it also uses Microsoft's new DeltaSync protocol. However if you're using a previous version of Outlook that connects using WebDAV, you'll need to upgrade to a new client that supports the Office Outlook Connector or reconfigure your client to connect using POP3.
Any users of Entourage on the Mac should also update their client settings to use POP3. Currently there is no alternative connection agent available like the Outlook Connector for Entourage.
Users who check their email using only the browser based version of Hotmail, will not have to make any changes to their account.