I have just discovered that same problem on a brand new XP Professional svc pack 2 machine running Norton Internet Security. <BR>
I have disabled NIS to no avail. Has anyone had this same problem and better yet found out why?? I have several other new machines <BR>
but have had no problems configuring a session using client access express.

The install of Service Pack 2 sometimes does funky things to the HOSTS file. Make sure that the HOST name is still in there pointing to the IP address. <p>Dave

We are getting a strange error with a couple of our Win XP systems. When installing CA v5r2 service level SI08894 we cannot use the 5250 client. Ops Nav works just fine but 5250 receives the following error: <BR>
"Host name not specified or not found." We have tried both the host name and IP address of the system to no avail. Also tried updating the hosts file. Uninstalled and reinstalled and forced registry removal. Anyone else seen this problem? <p>Scott

That was exactly the problem, Thanks much. This is odd since I had no problem with a few other machines - but then again we are talking about the Windows Operating System.