During the morning of January 25th, Microsoft was the target of a denial of service attack against the routers that direct traffic to Microsoft's web sites. As a result, access to some of Microsoft Internet properties, including Microsoft.com and MSN.com properties, was intermittent for many customers throughout this morning.
Microsoft's global networking team quickly determined that today's issue was completely separate from yesterday's outage, and has taken a number of steps to address the issue. Currently, all sites are available to customers.
This type of denial of service attack is not related to any Microsoft product. Such an attack is an attempt to interfere with the routers in one of Microsoft's Internet data centers. Microsoft's servers were running normally throughout the event, but the attack prevented access to some of Microsoft's web sites.
It is unfortunate that an individual or group of individuals would engage in this kind of illegal activity. Microsoft has made the FBI aware of this situation.
Microsoft has taken immediate steps to ensure our customers can gain access to our web sites. These steps will also make sure that our networks have improved protection from this type of attack.
We apologize for any inconvenience this has caused customers, and want to assure our customers that we will be taking further steps in the days and weeks ahead to further protect our customers and continue to provide a great web experience.