if Mac address then make sure you have attached Mac address and right portal and your Mac address starts with 00:1A:79..... and make sure you leave credential blank on you nox.
if username and password then make sure you removed your Mac address from NFPS site. generate new code if you can. your donation code is your username and password. its case sensitive and are sure no typo mistake.
ok so whatever portal you have on nfps site make sure you have same portal on your box. also, try to change country lock to all and reboot your system and see if that works.