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Derrick CreamerDerrick Creamer 

400 Bad SAML request?

Testing SSO but I just get "400 Bad Request. Your request resulted in an error. Description: Bad SAML request"

How can I troubleshoot this problem?
James McMahonJames McMahon
I use this tool quite a bit to get an idea of what is happening when trying to troubleshoot auth issues.

https://addons.mozilla.org/en-US/firefox/addon/saml-tracer/

Very good tool. 
Derrick CreamerDerrick Creamer
I figured out the reason:  StreamWriter was adding a zero-width Byte Order Mark to the start of the XML before base64 encoding, and Okta couldn't interpret the resulting XML auth request. (Thanks, James.)