Ah hoy, hoy.
I have this problem with Vista. Despite it being a load of crap, it is currently not allowing a program that communicates with TFTP unless I disable the Base Filtering Engine service, which isn't ideal because the Windows Firewall relies on this service to run.
I presume somewhere a port that this program uses is being blocked but I can't tell what ports Windows is blocking! Windows Firewall is disabled and so is Defender, so what else could be blocking this port(s)???
Does anyone know how to scan a Vista machine to show a list of blocked ports, or does anyone know how to configure this Base Filtering Engine?
Long shot, I know, but if you don't ask...