Hello, I have got following problem and would be happy about every hint you can give to me: Infrastructure: =============== A router (AVM Fritz!Box Phone 7050 connected via Broadband-Access to the WWW, using an dynamic IP adress. It's neccesarry to use this Router because it includes a VoIP-telephone switchboard with QOS-Features. External Adress: dynamic (WAN) Internal Adress: 192.168.178.1 The dynamic Address is published through a dyndns-Account After the router there is my firewall, (SuSE 9.3, iptables). The firewall is based on a "harry's script" which was a little bit modified. eth0: 192.168.178.100 (connected to the router) eth1: 192.168.1.100 (connected to my LAN) With IP 192.168.1.101 there is a Microsoft Windows SBS Server 2003 including Terminal-Server Service reached via MS-Remote-Desktop (Port 3389) ToDo: ===== The Terminal-Server should be reached from the www. This works fine as long as I don't have the Linux-Server in my network. If I change the MS SBS-IP to 192.168.178.101 for example and configure the router to forward all TCP 3389 requests to 192.178.101, everything works as it should. Problem: ======== After the Linux-Firewall is between router an MS SBS, Terminal-Server access is not possible (all client services HTTP, HTTPS, POP3, IMAP... work fine) I tried to ways: 1. Config the router to forward all TCP 3899 requests to the firewall (192.168.178.100) On the firewall i put the setting: iptables -t nat PREROUTING -p tcp --dport 3389 -j DNAT --to 192.168.1.101:3389 and (another try) iptables -t nat PREROUTING -p tcp --dport 3389 -j DNAT --to 192.168.1.101 2. Config the outer to forward all TCP requests directly to MS SBS (192.168.1.101) Firewall: iptables -A FORWARD -p tcp --dport 3389 -j ACCEPT On both way's a tried to include Source/Destination-IP, incoming/outgoing devices, but without any positive results. Which way I should follow generally? There get some packages through the firewall using both solutions (I can see an incoming connections in the Terminal-Servers log files) but no correct connection can be established. Thanks for your help