Problem with Live Messenger and ISA Server 2000

[arcturus]

Our office network uses SBS2003 Premium which includes ISA Server 2000. Our desktop PC's have been using MSN Messenger 7.5 both internally and with the outside world with no problems for some time, with ISA server configured as appropriate. I have just installed Live Messenger 8 Beta on a couple of machines as a test and whilst both machines can still browse the internet, neither can connect to the messenger service using Live Messenger 8. It looks as though it is being blocked by ISA server.

Does anyone know if the protocols have changed between MSN 7.5 and 8 and if so what do i need to tell ISA server to allow through?

[Saabyfox]

Are you using ISA 2000 in firewall mode in conjunction with proxy client, or in cache mode with the MSN settings for an http proxy ? Do you have ISA authentication checking on ?

MSN does port scanning anyway, and then tries various ports to communicate with an MSN server.
Firstly, leave the msn 8 client open even if it is not connecting as it will try numerous methods to get out ( its a crafty piece of software). Then if after a few hours it has not connected, trying using the diagnostics tool, as this also forces different connection techniques.

Microsoft change the server ip addresses of their MSN servers on a regular basis so its not easy to configure a firewall rule to allow/block it etc.

[arcturus]

We are in firewall mode with the firewall client installed on all the workstations. ISA auth is on.

I can now add the the Messenger 7.5 client has also now stopped connecting!! Most infuriating.

[BliarOut]

I have been having a few probs logging onto MSN just lately from home... It could, and I stress the could part, be a red herring.

I would be inclined to test a combination of versions/accounts just to make sure the problem isn't actually an external one. You might not have changed anything but MS might have.

[arcturus]

Sorted. On the problem machines, the firewall client had been set to 'Automatically detect the ISA server', except it wasn't doing so for some reason. When I explicitly set the name of the ISA server into the client, all was well. Just got to figure out why auto detection has stopped working. It used to work just fine!!