Ping problems

Since rebuilding XP on my desktop I cannot ping my laptop from the decktop but it's OK laptop to desktop via a WiFi router. Both Machines are XP and both TCP/IP setups are the same.
Regards
Gavin

 

Most obvious cause would be that they are on different subnets (e.g. 192.168.1.0 and 192.168.0.0), but both subnets are recognised by the router which can then route between the two subnets.

Check your IP addresses. You can use this tool to check that the addresses of the two PC will allow direct communication:

http://www.nicholshayes.co.uk/Node2Node.html

 

Thanks for the reply, the IP addresses are in the same sub-net ie 192.168.0.0, router 192.168.0.1, desktop 192.168.0.2, laptop 192.168.0.3, subnet 255.255.255.0 and only the rebuild of the desktop has changed but set remains the same. Any thoughts?
Regards
Gavin

 

How do the computers connect to one another, and/or the router. Which are using wireless.

If you have one of them with both wireless and wired connections, check your bindings. Swap them round and see if having wireless as the top bound adapter has an effect. Reinstalling may have changed your binding order, and that will effect how your network connection behaves.

Have a look at this post for more information on binding order.

 

The laptop has both wired and wireless (unchanged for last 6 months), the desktop has 1 x integrated 10/100 and 1 x PCI 10/100 all connections are set to receive IP from DHCP server (WiFi Router). The router is configured to allocate 192.168.0.3 to wireless laptop and .4 to wired laptop .2 and .5 are allocated to desktop integrated and PCI in that order. All subnet masks are set to 255.255.255.0. ARP tables show all connected interfaces.
This sort of thing used to be my bread and butter 'till I retired 3 years ago, I can't believe that I can't find the problem. Oh yes I have a sniffer package on both machines and the ping from lap to desk shows packets in and out on both but ping desk to lap shows outgoing on desk and nothing on laptop.
Please HELP
Regards
Gavin

 

Any firewall ?

 

Only XP firewall on both machines and on WAN connection (built in) on Netgear WGR616v2.
Regards
Gavin

 

I fall upon my sword. I committed the cardinal sin of replying before checking because we all know that we have fantastic memories.
Of course I believed that the problem was with the desktop as this was the one that had been updated. Not so, I had forgotten that I had Zone Alarm firewall and set to High on the laptop
Problem solved
Many Thanks
Gavin