The .NET program should use the name server to connect to the appserver.

When the developer use an IP address, then the connection failed (after waiting for a while).

When the hostname is used, than the connection is successful.

On other servers, both options (ip address/hostname) works.

Connection directly to the AppServer is also successful.

I have no clue what is going wrong here. I investigate the firewall etc. but no differences found compared to the other servers.

Any suggestions or ideas?

Progress OpenEdge 10.2B service pack 8.

Windows Server 2008 R2 Enterprise Service pack 1

Sample code:

string url = "AppServer://ip-address/appserver";
string username = "username";
string password = "password";
string connectInfo = "";
   mAppServerConnection = new Connection(url, username, password, connectInfo);
catch (Exception ex)