If you are getting and error message saying "Failed to engage firewall" or a Firewall Violation.
Make sure your Windows firewall is turned ON, then run Exam4 again.
If you cannot turn the Windows firewall on, your computer may have been affected by a virus which has impacted your Windows Firewall settings. Exam4 needs to engage the Windows Firewall, but if it has been altered by a virus, Exam4 is unable to do so. If you cannot engage the Windows firewall, you will need to either restore your computer to a time when it was working or have your operating system reinstalled so that it can be turned on.
You can also try Microsoft's FixIt tool. http://support.microsoft.com/mats/windows_firewall_diagnostic/.
Please let us know if you need additional assistance.