PC in DMZ not reachable from Windows 7

Dear Readers,

I am having a very specific problem for which I have (so far) not found a solution.

I have a small home network with several PC's via an Alcatel Speedtouch W780i Router modem. This modem has always had a bit of difficulties with assigning the DMZ via DCHP so I have chosen a static IP configuration.

Currently all the PC's have windows XP. One PC is configured as a server which I have placed in the DMZ. This PC has my WAN IP as ip adress in the TCP/IP settings. This cannot be changed and works perfectly fine.

All PC´s can see this server PC and access it via its hostname and IP and share files and printers with it.

I recently bought Windows 7 and (you guessed right) I cannot see the server PC in the network. It does not automatically list it in the network. I am able to access it when I type the IP in the file browser (but not when I type the hostname) and the shared folders do show up then. It still lists on all the XP machines or on the virtual XP mode of Windows 7 or when I boot into XP (I have dual boot at the moment). It clearly is a windows 7 specific problem.

I have my Windows 7 set to company network. I have set password protection off.

The only differences between the server PC and the other PC´s is the IP address and the gateway.

If you need any more information I´d be happy to provide it.

Sincerely,

Ryan

I've had a similar problem in our company network.
on a Windows 7 machine we were not able to start our intranet located in the dmz and remote desktop to a server in the dmz was also not possible from the windows 7 machine XP no problems.

I' added the routing table on the windows 7 pc and now everything works fine

go to the command promt
type route add -p xxx.xxx.xxx.xxx 255.255.255.255 yyy.yyy.yyy.yyy
were xxx is the ip address of the computer in the dmz and yyy is the ip adres of the gateway.
If you also want to connect by host name you can edit the host file located in c:\windows\system32\drivers\etc open the file in notepad and add the ipaddress and the servername at the bottem of the file
xxx.xxx.xxx.xxx servername

Hello Sparr009,

Thank you very much for your reply. I did as you described and I am now able to reach the PC via hostname.

However, the PC is still not automatically listed for filesharing and printer sharing as all the other PC's here in windows 7. The windows 7 PC also doesn't show up on the server PC (but does on all the other XP pc's).

The configuration of my XP pc's & windows 7 Pc is as follows:

IP: 192.168.1.XXX (where XXX differs per PC)
Subnet: 255.255.255.0
Gateway: 192.168.1.254 (IP of modem router)
DNS1: 195.121.1.34 (Primary DNS from my internet provider)
DNS2: 195.121.1.66 (Secondary DNS from my internet provider)

Server PC:
IP: XXX.XXX.XXX.XXX (My wan (internet) IP)
Subnet: 255.255.255.0
Gateway: XXX.XXX.XXX.XXX (Gatway of my internet connection, probably IP of modem/router of my ISP or something)
DNS1: 195.121.1.34 (Primary DNS from my internet provider)
DNS2: 195.121.1.66 (Secondary DNS from my internet provider)

I suspect that one of these settings must be conflicting. I saw that I was able to add a second gateway to the TCP/IP Setting, maybe that will work after a reboot? I have no clue :$ This is becoming pretty advanced for me.

Thank you very much for your help,

Ryan