TLDR: It may be because the certificate mappings are saved at the sub-application level, when in fact they are expected at the site or server level.
The setup is simple enough:
An IIS s...
Updated Apr 28, 2020
Version 6.0
Blog Post
6 MIN READ
IIS Client Certificate Authentication results in 401-Unauthorized for sub-applications
Thank you for this post - I was having this exact issue. Fighting so many issues to get client certs to work, this was the final one. I ended up moving the sub-app to its own site and then configured a many-to-one client cert mapping and success!