Just want to make people aware of a new topic recently posted by colleagues: Configuring MaxConcurrentAPI for NTLM pass-through authentication

This was written by the authentication product group team themselves and has a deep explanation of how NTLM pass through authentication works and how the MaxConcurrentApi setting affects it. This Wiki also provides links to the Knowledge Base articles for other content on NTLM MaxConcurrentApi, hotfixes related to it, and links to Technet blog posts on the topic.

Justin [MSFT]