Force Enrollment via logon script: Server unreachable, right now!

Force Enrollment via logon script: Server unreachable, right now!

I have set up force enrollment by adding the appropriate lines to my logon script, however when I log in as a user, I get a popup box that says "Server unreachable, right now!" The firewall is off on the server, and I am able to get to the web portal from the machine that gets the error. Any ideas?