Site-To-Site VPN & Exchange/Outlook 2000

[mapman04]

I just recently implemented a Site-To-Site VPN with the following configuration:

Host Site: Checkpoint NG (R55) on a Nokia IP130
Remote Sites: Checkpoint VPN-1 Edge Box

Full 1.5 MB T1s at all locations.

Exchange 2003 Server
Outlook 2000

Remote site users complain when they get an e-mail and try and open it, Outlook will lock-up for several minutes.

Is there a setting to change the MTU size in Checkpoint? I found several web pages saying the MTU should be lower than 1500.

I can recreate the issue, but never see anything in the log showing a problem.

If it try a ping 198.162.10.10 -f -l 1500 if get the packet needs to be fragmented but DF set error.

I've changed the MTU on the local PC but that makes no difference. Anybody have any suggestions?

Thanks in advance.

Mapman04

 

[rn4it]

Are you sure there isn't anything being dropped? We have a site that VPN's into us with a 512Kb connection. Setup a 2way tracker filter using the network having the issue and the server, to and from each other. Exhange uses some high ports that if blocked can cause a similiar problem. These ports can be hard set.