RDP problem L2tp

[marinh]

Hi,

We've set up an PFsense router (2.3.2) with 2 windows boxes on the LAN side (vlan). all are vm's.

Our customer needs an l2tp account on the pfsense box. When connected he needs to RDP to one of the windows boxes.

• l2tp works, we can connect
• We can ping both of the Windows boxes perfectly
• The windows boxes can RDP to eachother.

However, when we RDP from an l2tp client to a Windows Box, mstsc says "configuring remote connection" and after a while it says "Internal error".

We've already played around with MTU/MSS clamping, disabled NAT outbound, disabled firewall.

What could it be?

Thanks in adcance