Login fails with the message "SSO General Failure" when using a Control-M/Enterprise Manager GUI client 9.0.18.xxx in Compatibility Mode to an upgraded Control-M/Enterprise Manager server 9.0.19.200 when SSO is enabled.

Scenario:
Control-M/Enterprise Manager installation of 9.0.18.200 with SSO enabled.
Control-M/Enterprise Manager client and server are both 9.0.18.200.
After performing an upgrade of the Control-M/Enterprise Manager server to 9.19.200, it continues to work in Compatibility Mode.
Connecting a version 9.0.18.200 or 9.0.18.100 client to the upgraded Control-M/Enterprise Manager server fails with error msg "SSO General Failure"
The problem is on the the client side where the relevant information in the HTTP header response (which contains several keys -values) is not retrieved correctly.