No word on the specific cause of the problem, but Microsoft this afternoon said it restored access to the Windows Live services that had been unavailable to many people for much of the day.
Here's the company's statement:
Earlier today, an issue began that has caused some consumers worldwide to experience difficulty logging in to their Windows Live ID accounts. This issue has since been resolved and normal operations have been restored to all customers.
Microsoft customers experienced issues accessing various services that rely on Windows Live ID for authentication including Windows Live Hotmail, Windows Live Messenger and Xbox Live. We worked to identify the issue and have restored full normal operation to all of our customers. There is no danger of data loss or data compromise. It is important to note that the security and privacy of our customers was at no time compromised as a result of this issue.
Source:→ Todd Bishop's Microsoft Blog
Microsoft, Windows Live, Windows Live Hotmail, Windows Live Mail, hotmail, Windows Live Messenger, Outage