persistent SQLBrowser error eventID 3

I have what looks like a completed install of SQL Server Express Edition, accomplished via unattended setup as part of a custom application (on a machine hereafter dubbed Machine "A").

So far, though, I can't access this instance from a remote SQL Server Management Studio because SSMSE can't see the installed database engine.

I've verified that:

The SQL Server Express installation on Machine A has remote connections enabled.

The SQLBrowser on Machine A is enabled and running.

Machine A's Windows Firewall is disabled.

Using a test tool, I can see that UDP messages sent to SQLBrowser (on port 1434), arrive (i.e. it complains about their format in the System Log).

It seems that Machine A's SQLBrowser isn't responding to requests, but there's no obvious reason why.

There's one clue in Machine A's event log:

Whenever SQLBrowser is started or restarted, there's a warning in the App Log:

"The configuration of the AdminConnection\TCP protocol in the SQL instance SQLEXPRESS is not valid." (eventid 3).

Any help will be much appreciated.

Thanks in advance
Josh

Some more diverse testing reveals that the problem seems to occur only when SSMSEE is running on Windows 2000.

The source of the problem appears to be that W2K is not picking up the correct instance name (in other words, it puts MYSERVER in the list of engines, but not MYSERVER\SQLEXPRESS). If I key in MYSERVER\SQLEXPRESS by hand, things work as expected.

Incidentally, I noticed that when running under XP, the Network Server list shows which version of the SQL Engine is running on each server, but under Windows 2000, it does this only for very few of the servers.

Is this a shade of a known problem?

Josh