Authentication required, Browser session mismatch.

I am getting error message: 'Authentication required, Browser session mismatch.' anytime I try to do something in the administration section. Also when trying to pull out reports.

It is kicking me out and I have to sign in again but cannot actually Administrate 

We recently upgraded to the latest version of Sage CRM and apparently I can do what I need to be done when going to the non-https version of Sage CRM. The SSL Certificate works fine and it's setup seems ok and I don't know where to look now.

Thank you for helping me!