We have Exchange Server 2003 and remote office connecting through router to router VPN. Has about 7 Outlook clients onsite. The problem is only with one of them -- ocasionally it will disconnect from the Exchange Server and won't be able to connect for a while. When the person takes the computer home (it's a laptop) and connects to the VPN through WIndows network connections it works fine.
I can't even imagine where to start working on this issue.