Hi, I have a ISA server and i installed firewall clients in windows 9x and Nt.In Nt systems the users r not able to connect to yahoo messenger though i have created a protocol definition and protocol rule opening port 5050. before installing firewall the clients(nt systems) were able to login to yahoo messenger but now they r not. And when i login as administrator in nt systems iam able to login to yahoo messenger with the same settings. I've tried using yahoo's use proxy and firewall with proxy but its of no use.Pls help me. Regards Venkat Systems & Network Engg.