I've been using 199.85.126.10/127.10 (as forwarders on our Windows DNS server) and they have been blocking major Microsoft sites for the past week or two (off and on). "download.microsoft.com" was blocked off and on over the last week or so and the sites (or a site) behind Microsoft Update were being blocked yesterday (I tested on a separate machine with CS DNS & Google DNS). I also had trouble with "g.microsoftonline.com" (one of Office 365 sites).
Has anyone else noticed this? BTW, both download... and Microsoft update seems to be working now...
Thanks!
Bill