'MS SQL Server Connection' sample not detecting SQL Instance

[Steve]

I have been playing with InstallAware's 'MS SQL Server Connection' sample (which is pretty slick) and am findng some inconsistant behaviour in its ability to detect SQL instances and to display them in the selection dropdown on various workstations.
I suspect that this inconsistancy is not the sample project itself but rather some component or setup differences from workstation to workstation.
I have noticed that most of my XP workstations fail to detect an SQL instance even when the 'MS SQL Server Connection' sample is running from the same workstation that SQL Express is installed on. Running the Connection sample on Windows 2000 workstations seem to fair better in detection success.

Since I would like to integrate the ability to detect SQL instances across the network into my InstallAware project, I am hoping that you can explain to me what are the common issues that impact the 'MS SQL Server Connection' sample's ability to find and display such instances.
Hopefully by understanding what prevents the sample from locating a SQL Instance, I can obtain a better detection success rate in my installations.

Any advice is greatly appreciated!
Steve

[Gizm0]

The main cause is permission issues on Workstation.
If there is no Guest account (even with no shares available at alla) allowed to connect, then you can't enumerate what is running on the workstation.

[Steve]

Thanks for the reply Gizm0,
The Guest account appears to have absolutely no effect on the ability of the SQL Connection Sample to detect SQL Instances.
Whether the Guest account is disabled or enabled makes no difference.
Assuming that we are logged in with workstation Admin priveledges when running the sample would preclude the need for a Guest account in any case.

[jimo]

Try opening port 1434 UDP on the workstation you are installing on and the open 1434 on the other XP machines running an instance of SQL Server. The Windows 23k Servers running SQL Server should show up regardless.

[Gizm0]

Thanks for the reply Gizm0,
The Guest account appears to have absolutely no effect on the ability of the SQL Connection Sample to detect SQL Instances.
Whether the Guest account is disabled or enabled makes no difference.
Assuming that we are logged in with workstation Admin priveledges when running the sample would preclude the need for a Guest account in any case.

No no, you misunderstand my reply (i wrote it kind of wrong also, my apologies).

By guest, by guest account i ment anonymous access,the ability to browse without requiring user name and password.

Also on XP machines with firewalls try what jimo said.

[Steve]

Hey Jim,
Thanks for the reply!
Ok, I understand the problem now. I was opening a port for the SQL Browser on 1433 UDP not 1434 UDP.

So now I am getting the expected results with the 'MS SQL Server Connection' sample invoking the following firewall exceptions :
open port 1434 UPD including Internet
open port 1433 TCP local network

As always, thanks again Jim
Steve