It seems that Q&A messages are not retained when redirected through the authentication URL. This occurred twice when starting a new discussion here (as
well as to at least one other poster), though posting a reply worked fine on the first attempt (the second of four attempts at posting anything: new - failed, reply - success, new - failed, new - success).
The failed attempts at posting eventually redirected to a "page not found" page (which I didn't keep the URL of... sorry... pretty sure it was just a generic error page with a link to this forum).
I am using Chrome 10.0 (32-bit) on Windows 7 Professional 64-bit.
(As a general note, the redirect through https://login.live.com/login.srf?wa=wsignin1.0&wtrealm=... for every page on MSDN is slow and annoying, though generally not problematic.)
Later: I copied the text of this post before submitting, wisely it seems, since I was directed back to a blank "start a new..." page and the post was apparently not created. Take two...
Microsoft está realizando una encuesta en línea para comprender su opinión del sitio web de Msdn. Si decide participar, se le presentará la encuesta en línea cuando abandone el sitio web de Msdn.