This update caused some of Microsoft’s customers to remain locked out of their services such as SkyDrive, Hotmail, and Outlook. While Microsoft did manage to update their datacenter firmware without any issues in the past, the most recent attempt “resulted in a rapid and substantial temperature spike in the datacenter”, which sent the mercury high enough to kick off Microsoft’s safeguard process for a host of servers in the datacenter, which hence prevented users to access those mailboxes of theirs.
All’s well that ends well, and Microsoft has promised that something like this will not happen again. It should not anyways, considering the millions of dollars that Microsoft has poured in to advertise the Outlook.com service.