I have installed Freeradius 1.0.5 on the Redhat 9 machine. When I type the command" radtest test test localhost 0 testing123" to check ,the output is as the following: Sending Access-Request of id 252 to 127.0.0.1:1812 User-Name = "test" User-Password = "test" NAS-IP-Address = room129 NAS-Port = 0 Re-sending Access-Request of id 252 to 127.0.0.1:1812 User-Name = "test" User-Password = "S\306\212Go'\3216?!w\025\377\251\320," NAS-IP-Address = room129 NAS-Port = 0 rad_recv: Access-Reject packet from host 127.0.0.1:1812, id=252, length=20 Is this a proof that the Radius Server runs correctly? Then I run NTRadPing(a handy tool to test Radius Server on clients machines) on other machine which has Windows server 2003 OS, only got the results as follows: sending authentication request to server 202.117.x.x:1812 Transmitting packet ,code =1,id=2,length = 45 no response from server(time out),new attempt #1 no response from server(time out),new attempt #2 no response from server(time out),new attempt #3 could not recieve the response from the server I have configured /raddb/users and /raddb/clients.conf and had no effects. Then i configured /raddb/naslist, add winServer 2003 machines' ip and type as livingston, the problem is still not resolved. I don't know what difference between the types "Unix","Cisco","Livingston" and "Slaveport". Can anyone explain the difference for me?