I have 2 systems running Windows XP Pro and another running Windows 7 Ultimate. My windows xp systems talk to each other with no problem. I can share files between each other and print over the net work. When I try to add the system running windows 7 to the network I cant connect at all and the windos 7 system does not see the other 2 systems. I can access the internet on all systems but they cant talk to each other. I checked my settings in windows 7 and every thing is turnd on that should be on. The system with windows 7 is trying to connect through a wireless controller. I have a Linksys router N series. I can't seem to find help on line with this problem. Can some one help or have an answer.ThanksEric

This problem occurs if the Link-Layer Topology Discovery (LLTD) Responder component is not installed on the Windows XP-based computer. In order to establish the connection between the windows 7 machine and XP machine, try downloading and installing the Link-Layer Topology Discovery (LLTD) hotfix. Check the link mentioned below: Link Layer Topology Discovery (LLTD) Responder (KB922120) http://www.microsoft.com/downloads/details.aspx?FamilyId=4F01A31D-EE46-481E-BA11-37F485FA34EA&displaylang=en If this doesn't help, can the computer ping each other? To do this: Get your computer name (Visit http://windows.microsoft.com/en-US/windows-vista/Find-your-computer-name for help getting your computer name). In this example we'll be using Computer1 and Computer2as the computer names. On Computer1, Click Start, type cmd and press Enter In the black and white command box, type ping Computer2 and press Enter You should get something similar to the following: Pinging <###.###.###.###> with 32 bytes of data: Reply from <###.###.###.###>: bytes=32 time=77ms TTL=28 Reply from <###.###.###.###>: bytes=32 time=80ms TTL=28 Reply from <###.###.###.###>: bytes=32 time=78ms TTL=28 Reply from <###.###.###.###>: bytes=32 time=79ms TTL=28 If you get Request Timed Out, there's a something blocking communication between the computers. Try those steps out and let me know what works!also try reading this step by step article http://windows.microsoft.com/en-us/windows7/help/sharing-files-and-printers-with-different-versions-of-windowsIf you have have a firewall - disable it or configure it to allow communications between the machines. MCSE, MCSA, MCDST [If this post helps to resolve your issue, please click the "Mark as Answer" or "Helpful" button at the top of this message. By marking a post as Answered, or Helpful you help others find the answer faster.]

Hi Eric, Cdobbs's suggestion is worth to perform. In addition, you can also try the following steps. 1. Temporarily disable firewall on each machine and run a Ping test between Windows 7 machine and Windows XP machine. Can the computer get response from another machine? 2. Assure the following services are started on each machine: Computer Browser, Server, Workstation 3. Perform a Clean Boot on each machine. 4. Modify relevant settings on Windows 7 machine. a. Click Start and open Control Panel. b. Open "Network and Sharing Center" and click "Advanced sharing settings". c. Expand the current network profile (such as "Home or Work"), and then select the following options: "Turn on Network Discovery", "Turn on file and printer sharing", "Turn on sharing so anyone with network access can read and write files in the Public folders", "Turn off password protected sharing" Thanks, Novak

Novak,Thanks for getting back to me. I have tried every thing you sugeested and still I cant seem to connect to the Windows 7 system or sdd the printer to the windows 7 system. I ran cmd and was able to ping the system from my windows xp system. Do you have any other ideas.ThanksEric

Cdobbs,Thanks for getting back to me. I tried to down load the LLTD but since I already am running service pack 3 it told me that I cant install it. I was able to ping the windos 7 system from my other systems. The windows 7 system cant seem to find the network but yet like I said I can ping it from my other systems. Any other ideas.ThanksEric

instead of connecting the windows 7 machine to the xp machines can you make the win 7 machine the host computer and connect the xp machines to it? i know it shouldn't make a dif, but the 20mins it would take might be worth a try. and oron one of the xp machines, create a testfolder in the my documents folder, then open testfolder sharing settings through the rightclick properties and specifically share that folder. see if that folder shows up on the win7 machine. Again i don't think this will actually do anything but if it does work it may help narrow down the problem.

EricPost an IPCONFIG /all here from the win 7 and xp box here.post the make / model / firmware of the wi-fi router / card / usb you are using.are you using WEP if so switch to WPA2. WEP and N do not play well with win 7turn off IP6 on the win 7 wi-fi card.if the win 7 box is using IP6 it can access the Inet but the older IP4 boxes can not access it.