Strange sending problem

[MichaelCullen]

Hi

I'll start by telling you a bit about the setup

we have a Head Office and 2 sites. The two sites connect to Head office via a VPN tunnel over ADSL.

Each site has a Win2k server which is a file server, DNS and Wins.
At Head Office we have Win2k SBS server which is running File Server, Exchange, DNS, WINS.

All the workstations are WinXP with outlook XP to connect to Exchange.

Everything is running the latest service packs and patches.

Exchange is configured to send all external (internet) emails directly to our ISP.

Problem:

one site is fine and can send and receive internal and external emails with no problem.

The second site can send and receive internal emails and can receive external emails but can't send external emails.

I have checked in the message tracking center and I can find the emails and it tells me that they have been forwarded to our ISP but they never get to there destination.

i have spoken to our ISP and they have no problems with emails.

on the users workstation I can see the email in the sent items.

However if the same user uses OWA then the email get thru.

I have restarted the server in Head office but this hasn't helped and I'm now out of ideas.

This is driving me mad

any ideas?

Thanks in advance

Michael

 

[MaYHeM24]

More Info Please:

Are each VPN Subnet a part of your Active Directory? There is an option in Exchange to allow relays to users that authenticate. Why forward to ISP if your running SMTP and DNS Locally? Are both locations using a user account that exist in AD?

-=MaYHeM=-
-=IS MGR=-

 

[MichaelCullen]

Ok

I have now added the IP addresses to AD as none of them were there. Exchange is set to only relay the the IP addresses of the company but I have also tick the relay thoses who authenticate but this hasn't made any difference.

every one logs onto the network with a network login that is in AD

some idiot left the server as an open relay and we got hit and got black listed, and until I can get the IP address removed from all the lists i'm forwarding to our ISP. However I might change this and see if it solves the problem.

Thanks

Michael