When configuring the system to use ADFS/Azure AD, it is important to note that you may need to increase the Limit Request Field Size parameter. The size of a normal request header field will vary greatly among different implementations and authentication headers can be up to 12392 bytes.
For example when configuring ADFS, and if HTTP "400 Bad Request" errors
occur. Then the default value of the Limit Request Field Size parameter
has to be increased in the HTTP Server configuration in the Admin Console. The
picture above shows a recommendation how to increase this value, e.g. Set the
Limit Request Field Size parameter to the double of the default value.
Sometimes alse the Limit Request Line has to be increased.