Environment to reproduce:
Have a SAML server setup and working.
Using ADFS as a backend server.
SAML works for all users with other applications, like ITGlue.
SAML works for most users using Control.
Have user who is a member of 170 AD groups.
User can't login with SAML to Control. Just acts like he never pushed the button. Address bar URL ends with errorcode 6 after he clicks login with SAML.
SAML reply when replicating the issue comes through as expected.
Remove user from 40 groups and now it works expected.
SAML fails when user a member of too many groups
Customer support service by UserEcho