General Questions

I am running the latest version of m0n0wall on a Soekris net4801.

When I open a VPN connection from my Windows XP machine to the Windows Server at my work, I can't use Remote Desktop Connection to remote into the network.  Remote Desktop times out and reports a connection problem.

Does anyone have any ideas on how to establish a Remote Desktop session over a VPN connection to a Windows network?

You're going to need to be more specific.

What kind of VPN? Where is it terminated, the Windows server or m0n0wall? (i.e. what is the VPN server)

I am using the built in VPN client software that Windows XP comes with.  And the terminating server is a Windows 2000 RAS server on my companies network.

Everything works perfectly if I bypass the m0n0wall and access the internet directly.  So I know somehow the m0n0wall is blocking something or NAT isn't getting maintained...  but I can't figure it out.

An interesting side note: If I load pfsense on my net4801 using identical settings as I have with m0n0wall, everything works perfectly for both the Windows VPN connection and Remote Desktop as well as connecting using Cisco remote client to the Cisco VPN at my company.  However, then none of the site in my DMZ are accessible and I can't access the internet from my DMZ.

So for the time being it's a tradeoff of either having access to my work network, or having a functional DMZ.  Problem is, I need both!!

Well, all the problems you're discussing with both m0n0wall and pfsense are misconfigurations.

Though "Windows VPN client" isn't specific enough, is it PPTP or L2TP?

VPN problems can get really ugly to fix. If you would rather investigate your Internet from DMZ issue with pfsense, head to forum.pfsense.org. If you want to investigate your VPN issue, post back here.

I have experienced what sounds like the same issue using WRAP hardware and m0n0wall 1.231

I am accessing m0n0wall via PPTP using the Windows XP VPN client and attempting to connect via RDP to a Windows XP machine running under VMware on a Linux host. The RDP connection will occasionally work through the VPN, but most of the time I see only a black screen where a login prompt should be and the connection eventually times out.

The Windows XP machine is running on a 10.2.10.x address and accessing the outside through a 1:1 NAT. If I allow RDP traffic from the outside I am able to connect without issue.

Other traffic seems to work properly through the VPN (SSH, HTTP, etc.)

the described problem is caused by a MTU issue. I don't know what, nor how to fix or work around it.

Is there any further recourse? Can I contact the developer(s)?

I am also experiencing an issue when accessing the VMware Server Console through the VPN. I get connection errors while opening the port to the outside allows me to connect without issue.

It appears as though VPN on 1.231 isn't working quite right.