thanx for replyinh Uncle.... I m using Network Setup with Client Address Sets not with Domain right now...and I enable all protocols on ISA server and I also install ISA firewall client on Client PCs !!! Thats Enough! and everyone is getting voice easily? But Uncle my problem is that If I select only Selected Protocols then Web2sms or Web based chat do not work properly thats why I have to enable all protocols but this is drawback for me that most of the users are getting voice service that which should not work on my clients? Again I m giving you the web address of these Web2sms Sites like http://wwww.instasms.com/smschat/ and http://vega.vectracom.net/webchat/ . How Can I stop these problems ? Plz try to understand my problem!!!