@motorollin:
Is your router usuable as a dns-server by other computers on your network?
If not, try using the dns supplied by your isp.
With AmiTCP up to version 3.0b2 you specify the nameserver(s) in the file AmiTCP:db/netdb-myhost, in later versions in the file AmiTCP:db/resolv.conf.
Thosee files should be supplied with examples, ending with .example or -example.
/Patrik
