PC Not Visible From One PC in the Network

Topic

New Reply

Network:

• Linksys BEFW11S4, WEP w/no broadcast, signal strength is displayed as “excellent” on the two wireless PCs
• Vista Business (SP1), Dell Vostro 1700, Wireless [VB-1]
• Vista Business (SP1), ThinkPad, Wireless [VB-2]
• Vista Ultimate (SP1), ThinkPad wired [VU]
• Brother printer wired
• Notes: All PCs have file & print sharing enabled, Both IPv4 and IPv6 are enabled on all PCs and both IPv4 and IPv6 addresses are displayed
  [/list]Norton Internet Security:
  All IP addresses are setup as Trusted on each PC’s firewall. While this is not really necessary, I found that this solved some earlier access problems.

  History:
  All PCs have been able to access each other.

  Problem PC:
  Vista Business (SP1), Dell Vostro 1700, Wireless [VB-1]

  Status:

  • All PCs can access the Internet
  • VB-2 and VU can access each other and VB-1
  • VB-1 can see VB-2 but not VU even though the network map shows all three PCs with the same IP addresses as the router shows. The error “network path not found” is displayed when trying to access VU.
  • When VB-1 is connected wired, it can access all PCs on the network.
  • When hovering VB-1 and VB-2, the cursor changes to a hand. However, the cursor does not change when hovering over VU but the info pop-up is displayed (Name, IPv4 & 6 addresses and MAC address).
  • For some reason, sometimes when the Network Map is refreshed, all PCs disappear off the map except for the PC being used. Those disappeared PCs are put at the bottom in the “cannot be placed on the map” section. Refreshing the map again displays the “lost” PCs.
    [/list]VB-1 actions taken (that I can remember):
    • Disconnect – reconnect
    • Disable – enable
    • Uninstall – let Vista re-install
    • Remove all previously discovered-and-connected-to networks (Manage Wireless Networks window)
    • Check Connect even if the network is not broadcasting (Wireless Network properties window)
    • Run diagnose and repair – just ends up showing Network path not found
      [/list]My greatest frustration is with VB-1 since I cannot access VU. This is especially important since all our backups are sent to VU.

      Any other actions I can try? I suppose that I could back out recent Windows updates one by one and see that changes anything. I haven’t done this since these updates are installed on all PCs and only VB-1 exhibits the problem.

      Thanks,

Reply | Quote

Replies

One thing that I would definitely try is completely disabling all firewalls.

DON’T leave them disabled after you finish testing, this is just to make sure this is not a firewall configuration issue.

StuartR

Reply | Quote

Okay. I disabled all firewalls and all PCs were “happy” as Emeril says. Then I re-enabled the firewall on VU and VB-1 couldn’t access it anymore. I checked the VB-1 NIS Trust center and discovered that I had not setup a trust relationship for VU’s IP address on VB-1. I did and everybody’s happy again.

So, it turns out that I really do have to set up firewall trust relationships for all IP addresses assigned by the router. I never had to do this before. I am using a different service provider at this location (Comcast) than I was at the other (EarthLink) but that shouldn’t make any difference, should it?

Thanks, – Al

Reply | Quote

Glad to hear you have it sorted. Thanks for giving such good quality information that I could guess at the cause.

StuartR

Reply | Quote

Thanks for your help. Isn’t it interesting that the firewall was no problem when VB-1 was wire-connected and yet wireless it exhibited the no-access behavior?

Reply | Quote

When you connect via wireless you are effectively connecting via a different network route, so the firewall will treat you differently.

StuartR

Reply | Quote