iCamSource/iCamSource Pro does not currently support Windows Server, however here are a couple of things you can check:
Is your webcam plugged into a USB hub or extension cable? If so, please try plugging it directly into the computer.
Make sure that Windows is fully updated through Windows Update and that you have the latest drivers installed for your webcam.
Also, please make sure there aren’t any other video capture programs (such as Skype) running. They might be fighting iCamSource for access to the camera.