I think something else is happening here.
He tells, that it is a valid certificate from Symantec
I am using a valid third party certificate provided by Symantec Corporation
Maybe we are mixing stuff up.
on which server do you have installed that certificate?
on the running server, that run’s the headless-client? and the headless client is trying to get an url from another server with ssl??
So please explain a little bit more, the whole setup.