Sending messages with attachments over VPN

[Mark]

Hello,

I have setup a VPN which seems to work ok, there is
however one slight problem. When the user sends an email
over the tunnel with a small attachment it goes through
ok, if they attempt to send a message with a large
attachment, say around 7MB, then the message doesnt go and
tends to make Outlook hang before giving an RPC error.

Does anyone know why this could be?

Many thanks,

Mark

 

[Greg Mansius [MSFT]]

Mark,

It might be a problem with a black hole router. The resolution is usually a
manual change to the MTU size on the client. Please see the following
article for details and tshooting info.

314825 How to Troubleshoot Black Hole Router Issues
http://support.microsoft.com/?id=314825

Hope this helps.