I've been dealing with this problem for a few days now, and I'm sort of stomped, here's the situation.
I recently installed a file server at one of my clients. The setup is pretty simple:
DSL Modem --> LinkSys Router/AP --> Dell 24 port unmanaged switch
One DELL PowerEdge Server connected to straight to the linksys router Running Windows Standard Server 2003 with DHCP , WINS and Internal DNS
All clients (6 clients) connected through the Dell Switch.
The problem I've been having is this:
I've opened up a port in the router for Remote Desktop (in administration mode), so that I can manage the box remotely. what's happening is that randomly, I'd be in an RDP session, and *wham* I lose connection.
I tried installing VNC and opening the appropriate port, to see if I can isolate the problem to RDP, but the access has been blocked completely to server services.
I still haven't tried to:
Try to have a service other than remote access open (i.e. IIS) to the internet to see if this service gets blocked as well.
Here's the troubleshooting I've done so far:
I've verified that when I lose remote access to the server, that I am still able to access the gateway from WAN. (the LinkSys Router) - CHECK
I've verified that when I lose remote access to the server, that the server is still live ... I was able to ping it from the router - CHECK
I've verified that I'm not able to access the server via RDP and/or vnc from several remote workstations, to make sure it's not a problem with my client - CHECK
I've verified that Windows Firewall is turned off on the Server - CHECK
I used to have the Hamachi VPN software on there, which I initially thought might be causing the problem, so I uninstalled it - CHECK - Problem persisted.
When the problem happens, I'm usually not on site, so I've asked my client to try to connect to the server via RDP from within the LAN, and it DID work. so connection via WAN only is not working. - CHECK
Current Workaround: reboot the server, and everything is back to normal.
So far I've experienced the problem happening while I'm in a remote session, RDP or VNC.
My guess of the problem right now is evolving on a problem, primarily, with the server itself, or perhaps, the router (??doubtful though??)
Thank you in advance for any help you can provide.