I got this error when I fired up Peoplesoft signon page for the first time after a fresh install. The Message is misleading as I was unable to find anything in the app server logs. So what is the cause?
It turns out that the password for the user (PTWEBSERVER in my case) that is used to start the web server was not correct in my configuration.properties file.
I updated the password (you have to change and encrypt it) using instructions from here and bounce the app server and web server. After that everything was working as expected.