Microsoft Web Sites Down for Hours

Problem linked to domain name resolution conflict.

Several online news organizations, including, have reported that Microsoft's corporate Web sites worldwide have been inaccessible for hours. Sites affected include,, and

Some sites were back up early this morning, but the Microsoft Training and Certification site at was still inaccessible as of 11 a.m. Pacific time.

Andy Barkl, MCSE and president of A&E Computer Consulting in Glendale, Arizona, recognizes it to be a DNS name resolution problem of the DNS name servers in the domain.

"I try to connect to Microsoft's DNS servers with nslookup, but I can't list anything," but Barkl says it's unlike a query refused error. "I can connect to all Microsoft Web sites and newsgroups with the IP address, so it seems that the whole * is affected."

"If Microsoft's Primary DNS zone (server), which they maintain, is off line or unavailable, this would explain the unreachable errors," he explains.

That some sites are back on line means that Microsoft has likely fixed the problem, but the sheer size of Microsoft's Web site infrastructure means that the correction will take hours to rectify. "Although it is easy to transfer ownership of a Primary DNS server to a Secondary DNS server, the off-line problem probably reaches deeper into the company's network infrastructure on which the DNS servers reside. Modifying network routes and waiting for convergence, can take time in a network such as Microsoft's."

As to what caused it, Barkl jokingly says it's anyone's guess: "It may be hackers; it may be their rollout of ISA Server; it could be an Active Directory problem." Reports have slowly surfaced in the media that a handful of the company's global Web sites have been hacked and defaced in the last few weeks.

For the complete story from CNET, go to


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