I have 3 Windows 7 (x64) machines and a Windows 2003 R2 server on the same network. They all belong to the same network. Currently, I have the firewall turned off on my main Win 7 machine (for testing purposes). The main WIn 7 machine can (usually) see the other 2 win 7 machines in 'Network' (having said that, all the other machines are currently not shown, but that's unusual) I can enter a network path in the address bar to any machine and it works. Usually, this does not make the machine appear in the network list (but just now it did). The other 2 Win 7 machines can see all the machines in the network. The 2003 machine can see 2 Win 7 machines but not my main machine. No machine on the network can ping my main machine, but all other machines can be pinged from it. I've spent a long time Googling but not found any solutions or even a good understanding of what might be going wrong. ANy help much appreciated! Iain I can ping all the other machines Iain Downs

Hello Iain, if you dont need IPV6 i recommend you to disable ipv6: Control Panel\Network and Internet\Network Connections :R.C properties then uncheck Internet Protocol version 6. try TCP/IP Stack Repair: Start Command Prompt, select "Run as Administrator" to open a command prompt. netsh winsock reset catalog netsh int ipv4 reset reset.log netsh int ipv6 reset reset.log Please let me know if you solved the problem :) Abeer Omar, MCP,MCSA,MCSE,MCTS.MCITP

Thanks for your suggestions, Abeer. I've done as you suggested and rebooted the machine. Unfortunately, it's had no apparent effect on the problem. What confuses me most is that I can't ping the machine from outside. And with no firewall in place! IainIain Downs

Is there any software installed on the problematical machine that isn't installed on the others? I'm thinking of something like a security suite or networking analyzer - something that might interfere with or tie into the network driver and block or redirect incoming ICMP packets.

Check your network settings and make sure your main machine is on the same subnet as the others. If in doubt, please post the results of an ipconfig (no need for the /all in this case) from your main machine and one of the others.

HI, Bob. Yes. the machines are all on the same subnet. They are all on 192.168.2.X. The subnet mask is 255.255.255.0 in all cases. All machines use DHCP from my router (on 192.168.2.1). It's worth noting that the difficult machine can ping all the other machines - they just can't ping it. IainIain Downs

There are two things which fit in that category. VMWare and Virtual PC, which have been on for a while, but VMWare does update itself from time to time. I have tried disabling the VMWare elements in the network connections properties, but this had no effect. I've also recently installed a Checkpoint VPN client for connecting to a client. I've also tried disabling that (or at least shutting down the client), but again this has had no effect. I shall try uninstalling this and reboot and report. As this is a development machine I have over the couple of years its been alive installed any number of programs on it (more than I can reasonably remember!), so there could easily be something having a nasty side effect. I know that I've had inconsistent views of network machines in the past - usually it seems to me the machines with the same level of OS can see each other and that those with differing levels run some kind of random lottery. But it seems to me that this has got worse recently. THe inability of my W2003 machine to see the Win7 machine is definately new; I backup the Win 7 machine from the 2003 machine - in fact that's one of the things that triggered this investigation. I also have the impression that the ping problem is reasonably new. I believe that I've access the web server on this machine from others in the past. Mind you I can't be certain of that. IainIain Downs

Thanks, Bob. I've uninstalled (not just disabled) the Checkpoint VPN client and the machine seems to be working fine again. I can ping it and it can see all machines on the net from it and my W2003 machine can see it. So Checkpoint seems to be the cuplrit... IainIain Downs

Glad you find the culprit. Regards, MiyaThis posting is provided "AS IS" with no warranties, and confers no rights. | Please remember to click "Mark as Answer" on the post that helps you, and to click "Unmark as Answer" if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.