Home network stopped communicating

By sscohen0623 · 36 replies
Apr 2, 2008
  1. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +184

    no need to install LookLAN elsewhere. A couple comments/questions first
    1. Mcaffee Network Mgr IDs that is your printer
    2. Mcaffee Network Mgr IDs which isn't seen elsewhere.
      • If you look again, is it still there or disappeared?
      • If still there, do you have any other network connections (e.g. bluetooth) that aren't connected to your LAN ethernet cables?
    3. Do you mean from Office9100? So you're saying when you look from Office9100 at My Network Places it sees all 5 computers (counting itself)?
    4. LookLAN is installed on Office9100, is that correct?
      • So you mean from Office9100 you can see all 5 computers from My Network Places but LookLAN on that same computer doesn't see all 5??
      • Could you verify this oddity again? And check the Port scan range you are using in LookLAN

    Also, could you remove the ISP cable from the router and turn off all the firewalls on all the computers. Wait 5-10 minutes and check LookLAN and My Network Places per Computer again

    /***** Edit ****/
    And which computer is McAfee Net Manager running on?
  2. sscohen0623

    sscohen0623 TS Rookie Topic Starter is there. I do have a Bluetooth receiver attached to the computer "TV" for a Bluetooth mouse. It’s located in the next room.

    Office9100 is my main computer and OFFICEMAIN is the workgroup. I can see from office9100 the workgroup and all 5 computers including office9100. But get the error message when I click on any of the 4 other computers.

    look@LAN is installed on office9100. Yes I can see all the computers on office9100 but look@lan does not.
    New scan range to
    Same results.
    Proof scan results for are
    135 loc-srv NCS local location broker
    139 netbios-ssn NETBIOS Session Service
    445 microsoft-ds -
    1025 listen listener RFS remote_file_sharing

    I will turn off firewalls, wait and check look@LAN again.
  3. sscohen0623

    sscohen0623 TS Rookie Topic Starter

    OK it works now! Didn't do that when I did the same thing before. Turned on all the firewalls and it still works.

    Ran look@lan with firewalls off and it saw all. ONLINE Same LAN NOT WIN - - - - - ONLINE Same LAN WINDOWS HP0015604736B4 000000CFA24A (n/a) - - ONLINE Same LAN WINDOWS JAMIES JAMIES (n/a) - - ONLINE Same LAN WINDOWS TV TV (n/a) - - ONLINE Same LAN WINDOWS LAPTOP-PC LAPTOP-PC (n/a) - - ONLINE Same LAN WINDOWS LAURA LAURA (n/a) - - ONLINE Same LAN WINDOWS Office9100.nv.charter.com OFFICE9100 (n/a) - -

    But after turning on the firewalls ran it again and it was the same results as before. Didn't see the others. But now I can access the other computers.

    Thank you so much for your help. What do you think was the problem? new router cause the firewalls to reset?

  4. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +184

    I think LookLAN is relying on ping to identify other computers (a network message asking the computer at other end to reply to command). Firewalls may block ping (so no response is sent) to prevent hackers from finding the computer when hackers generate pings to a pre-programmed range of network addresses just to see who replies.

    Certainly, your router shouldn't reply to ping (on the WAN side). It can reply to pings on the LAN side. Am guessing the firewalls on the computers are blocking ping.. but i don't think it's necessary to block on computers on the LAN side (any reader's want to comment?)

    In any case, just affects LookLAN and what it seems to report. Having it available to reliably report on the other IPs on your network can be useful tho.. so might consider if ping should be blocked by each computer on your LAN or allow them to reply

    Computer Access via MS Network
    i have seen where changes in MS Network in response to firewall changes may take a bit of time (but within 5-10 mins certainly) so keep an eye on things for the next short while.

    Otherwise, not for certain all the issues that triggered this tho sounds like, in fact, you had a master browser issue that started it all off. I haven't looked yet myself but sounds like looking into using browstat (tipster mentioned) and other MS tools for browser issues is good to know.
  5. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +184

    btw.. if you open a cmd window (Start->Run, enter cmd, hit Return. Works for XP computer. Need admin priviledge on Vista), then enter
    ping (which happens to an address for google). or try your LAN ping to try and ping Laura

    You might find it interesting to try entering tracert as well.
  6. sscohen0623

    sscohen0623 TS Rookie Topic Starter

    ok all is not well. I lost access to the others except TV. I pinged other computers and it timed out and then checked. The only one I can see now is TV. What gives?
  7. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +184

    its gonna be related (at least part) to the firewalls.. turn 'em off and viewing and access among everything in MS Networks is good. Turn firewalls on and problems return. AND the change in MS Networks isn't immediate after firewall change. It takes a short while for firewall transition to affect MS Networks.

    Could you list, by computer name, what firewall software product is running on the computer.
  8. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +184

    and actually if we just turn off ping blocking on each computer LookLAN can tell us which ports it sees open on each computer which could help tell which computer firewalls are blocking ports)

    And note LookLAN (i would think) always see the ports on the computer its running from as open (even if firewall blocked). So would still need verify Office9100 after running LookLAN from it to verify ports on other computers

    Hey, but at least looks like its closer (and btw... you do remove the WAN cable from router when firewalls are off? just to make sure nothing gets thru to computers from outside when firewall protection is off)
  9. sscohen0623

    sscohen0623 TS Rookie Topic Starter

    I went into the firewalls and added the IP's to my firewall. I have mcafee on all and also windows firewall.
    After doing this i'm back to ok.
    Just have the permission issues with the 2 vista computers.
  10. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +184

    ok.. good deal.. yea, those firewalls are good protection but sure can be a pain to maintain! (btw.. is LookLAN doing better at seeing other IPs as well?)

    i've gotta go offline.. will try to follow up still this evening if can, otherwise tomorrow.
  11. sscohen0623

    sscohen0623 TS Rookie Topic Starter

    Yes look@lan sees them all now.
    I can't thank you enough.
  12. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +184

    good morning!

    To help get your vista computers setup correctly (as well as maintain your XP computers) I've included some links that talk about File and Resource Sharing across XP Pro, Vista and Media computers. I think it'll cover all the info you will need. if you're having a problem, just post back to the thread.

    In fact, appreciate if you post back if it works as well... Be good to hear for certain one way or another.
    And one question... we talked briefly yesterday about what issue(s) could have caused all your problems. And i do think it was a combination of things that hit you.

    Master Browser issues were one. And i could see how if your LAN wasn't set correctly to assure there would be only one Master Browser, then it would be just a matter of time and chance when the problem hit you.

    But thinking back on the firewall issue.... WHen you say you added the IP, was it there before, but missing now? or you added an IP saying allow all traffic from this IP? I guess the bottom line question (if you might now) were the firewall settings different now (with the problem) then before (when no problem). Answer is less important now that everything works, but trying to think how you might work before if the firewall was indeed blocking traffic.

    Just curiousity.. most important, is that its fixed (or very close to being all fixed!)
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