These are the official Microsoft forums listed by site, or by forum platform. The size does not include archived forums. Add any additional forum sites that are owned by Microsoft.

Site Description Size
ASP.net

Web development

 62 forums

Bing

Topics: Developer, Maps, Search, and Webmaster  17 forums
Channel 9 Topics: Coffehouse (chat), Site Feedback, Tech Off, The 9 Guy Around the World, and The Sandbox  5 forums
Community/Answers  Includes Windows, Office, IE, Live, Zune, and Hotmail  9 forums with filters
Dynamics

Topics: GP, AX, CRM, RMS, SL, NAV, Introductions, Jobs, Feedback, and more  15 forums
Expression

Categories: Moderators, Blend, Design, Web, Encoder, Studio, Media, WPF, Feedback, and Sandbox  19 forums
IIS.net

Topics: Versions, General, Troubleshooting, Security, Setup, Publishing, Web Platform, and more  29 forums
Microsoft

Categories: Using Forums, Moderators, Learning, Dynamics, Live Mesch, Microsoft Resarch, Genuine Advantage, Academic, HPC, Windows Home Server, Windows Live, OneCare, Windows Phone, Archived, and more  112 forums
MSDN

Developer/release forums

 432 forums

Office 365 Categories: Directory Integration Services, Downloads, Email, IM, Service Admin, Office Pro Plus, Web Apps, Blackberry, Upgrade, and Websites  36 forums
Silverlight.net

Topics: General, Programming, Data and Service Dev, Gaming, Mobile, Design, Other

 21 forums

TechNet

Resources for IT Professionals

 432 forums

 Xbox

Questions about Xbox Live, games, support, Live Arcade, and more.

 2,000+

 

NOTE: This topic originated from a forum thread.