Microsoft-related Knowledge Bases

Link	Description
Brian Madden	Great resource for Citrix, Terminal Server, Bear Paw, and Thin Client information.
BrienPosey.com	Nice articles and tips by Brien Posey.
Computer Performance	Nice articles and tips by Guy Thomas.
EventID.net	The Event ID database contains thousands of event IDs and comments provided by thousands of contributors. Needs a subscription but non-subscribers will get what they want too, and it's sure worth the pennies they're asking for.
Events and Errors Message Center	Find detailed explanations, recommended user actions, and links to additional support and resources for Microsoft products, such as Windows 2000/XP/2003, Exchange 2000/2003, SQL Server and Office products.
FAQ for WindowsOr here: FAQ for Windows	Formerly known as John Savill's NT Faq. Many tips for Windows NT/2000/XP/2003. Although many tips are in fact copied KB articles, the ones that are there are hand-picked and easy to find.
JSI, INC. - Tips & Tricks	Like NT Faq, one of the first and finest tip repositories, with thousands of Windows NT/2000/XP/2003 tips and tricks.
kbAlertz	kbAlertz.com is an e-mail notification system that scans the entire Microsoft Knowledge Base every night, and e-mails you when updates or additions are made to the technologies you subscribe to.
LabMice.net	"If you work with Microsoft Operating Systems and Server products, this site is designed to save you time by helping you rapidly locate hard to find technical resources. You no longer need to scour through irrelevant search engine queries, and dig through a dozen different technical sites for information. We hand pick the best technical articles from hundreds technical sites and index them here by category and topic. Whether you're writing a disaster recovery plan, troubleshooting a blue screen error, or defending your network against hackers, start your research here. We're confident that we can help you find the answers you need faster, and with less hassle, than anywhere else on the web."
MDGX Max Speed	Used to be AXCEL216, now calls himself MDGX, but still has hundreds of great tips.
Microsoft Download Center	As the name implies - Microsoft-related. If it's public, you can find it here.
MSDN Home Page	Home for Microsoft's MSDN library.
Microsoft Exchange Server resource site	Also known as MSExchange.org, this is a very good resource for Exchange-related articles and whitepapers.
myITforum.com	Great resource for IT experts, loads of articles and tips neatly divided into subjects.
ProcessLibrary.com	ProcessLibrary is an invaluable resource for anyone who wants to know the exact purpose of every single process.
Search the Support Knowledge Base (KB)	If you need a Knowledge Base (KB) article and Microsoft has made it public - you'll find it here. See my MS Knowledge Base Search Tips page for more info.
TechTutorials	Free technical articles with reference to some of the best knowledge bases around. Articles are updated weekly, well worth visiting.
The UltraTech Knowledgebase Viewer	A very good knowledge base for MS-related articles written by Andrew S. Baker, one of the most active forum and mailing list participants there is.
Windows NT-2000-2003-XP Admin Knowledge Base	Used to go with a different URL, now totally re-organized and has tons of useful articles and tips.
Microsoft Windows XP - Command-line reference A-Z	Detailed information about the Windows XP (not just XP, also good for W2K and Win2003) CLI. In addition to the built-in tools, there are over 40 support tools included on the Windows XP/2003 CD. You can use these tools to diagnose and resolve computer problems. For more information about these support tools, see Download Windows 2003 SP1 Support Tools and Download Windows XP Reskit Tools.
Windows NT/2000/2003/XP Admin Knowledge Base	Part of Windowsnetworking.com, a selection of hundreds of great Windows-related tips and articles.