To give you all a basic over view of our configuration, we have two sites setup connected through a VPN and we have no problem communicating with devices on either side of the VPN tunnel. Site A has an Exchange 2003 server configured which actually contains the mailboxes. At Site B we have an Exchange 2003 server configured as a front end server, all email traffic comes into this server and gets passed out to the corresponding exchange servers.
The problem is, the exchange server with the mail boxes at Site A is sending data to the front end server and is using all available bandwidth. We have another site, Site C configured exactly the same as Site A, but it's not having any such problems. This problem has been going on for about the past month or so, prior to that this configuration has worked without this issue for the past 2 years.
I restarted the Exchange services which temporarily fixes the problem but approx 24 hours later, it starts up again.
I have no idea what information is being sent, no one has informed me of any large emails that have not been able to send. There is a 3 Mb pipe between sites and the email size limit is set to 50 MB so it shouldn't be a large email attempting to send.
Has any else experienced a similar problem or know where to start looking to solve this problem?
Thanks for any help.