Member Avatar for alangef

Situation is:
Desktop PC has 2 ethernet card, one is auto IP. another is
Laptop has 1 card, IP is

From Desktop ping ,everything is OK.
From Laptop ping , "Request time out"

Please help me.. I am looking for your kind reply, THANKS!!!

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  • Latest Post Latest Post by abcde12345

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As described, the desktop has two network adapters and the laptop is directly connected; pings work in one direction only. Replies from , and covered the usual quick checks, so below are focused diagnostics and practical fixes that resolve this exact symptom on Windows XP machines.

The most common root cause with dual‑NIC desktops is asymmetric routing: Windows chooses the outgoing adapter by the routing table and adapter metrics. If the two adapters sit in overlapping subnets or the wrong adapter holds a default gateway, reply packets can leave via the other NIC and never return to the laptop. A host firewall can also silently drop ICMP replies, but routing is the usual culprit here.

Run these commands to gather facts (on the desktop and the laptop as indicated):

ipconfig /all
route print               # on the desktop, inspect routing table and interface list
arp -a
netsh interface ip show config
tracert <desktop-IP>     # run on the laptop to see where packets stop
nbtstat -A <desktop-IP>  # run on the laptop to check name/MAC resolution

If a quick test (temporarily disable the desktop's other NIC or unplug its uplink) makes the laptop->desktop ping succeed, routing is confirmed. Fixes that have worked reliably:

  • Put the private laptop<->desktop link on its own distinct subnet (different from the uplink DHCP range).
  • Do not set a default gateway on the private adapter; leave the gateway only on the adapter that should reach the Internet.
  • Set adapter metrics manually (TCP/IP Properties → Advanced on XP: uncheck Automatic metric and assign lower metric to the preferred uplink).
  • If Internet sharing is required, use proper Internet Connection Sharing or NAT rather than dual identical subnets.

These steps address the asymmetric-reply behavior without changing physical wiring.

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Member Avatar for ramwire

Ok these might sound silly but here it goes:

1. Are you sure that the network cable coming out of the laptop is connected to the network card of the PC with the IP and not the other auto-ip one.

2. Is there any firewall (built-in or otherwise) on the desktop that could be blocking the ping requests coming in from the laptop.

3. In the laptop, try setting the default gateway as if you haven't done it yet. I assume you'll be able to do that, but if you need further instructions on this let me know I'll try my best.

Ok I hope that was somewhat helpful.

Ciao for now.

Member Avatar for alangef

Ok these might sound silly but here it goes:

1. Are you sure that the network cable coming out of the laptop is connected to the network card of the PC with the IP and not the other auto-ip one.

2. Is there any firewall (built-in or otherwise) on the desktop that could be blocking the ping requests coming in from the laptop.

3. In the laptop, try setting the default gateway as if you haven't done it yet. I assume you'll be able to do that, but if you need further instructions on this let me know I'll try my best.

Ok I hope that was somewhat helpful.

Ciao for now.

Thanks for your on time reply... All the questions you asked that I did the right way. BTW: Both Desktop and Laptop are XP systems.

Member Avatar for ramwire

I'm sorry I didn't understand your reply fully. Are you saying you already tried what I wrote and you still have the problem?

Member Avatar for alangef

I'm sorry I didn't understand your reply fully. Are you saying you already tried what I wrote and you still have the problem?

Exactly. I tried everything you wrote... :(

Member Avatar for alangef

Exactly. I tried everything you wrote... :(

UP........

Member Avatar for steveneven

You have 2 NICs in one machine, you have assigned an IP to one of them, and something else is assigning the IP address to the other one, what is supplying the dynamic address?

Is this router/hub/gateway/ADSL modem? (Or other???)

How is the laptop connected to the desktop, are they individually connected to a hub or something?

SE

Member Avatar for alangef

You have 2 NICs in one machine, you have assigned an IP to one of them, and something else is assigning the IP address to the other one, what is supplying the dynamic address?

Is this router/hub/gateway/ADSL modem? (Or other???)

How is the laptop connected to the desktop, are they individually connected to a hub or something?

SE

Before I installed the new PCI netcard, the old one in the Desktop is connected with the hub of mine. The IP of it is automatic assigned. It worked normally. Now, I assigned the IP of the new netcard in my Desktop.

It is hub here, it connect with a cable modem.

The laptop is direct connected with the desktop, through one crossover cable, card to card, right?

Member Avatar for DMR

1. Why the hub? If one of the NICs in the desktop is connected to your cable Internet connection and the other is connected to the laptop, I don't see where the need for the hub comes in (unless there are other machines involved which you haven't mentioned yet).

2. Have you set up ICS (Internet Connection Sharing) between the desktop and laptop yet? If not, you should do so.

Member Avatar for abcde12345

:cheesy:

Ok these might sound silly but here it goes:

1. Are you sure that the network cable coming out of the laptop is connected to the network card of the PC with the IP and not the other auto-ip one.

2. Is there any firewall (built-in or otherwise) on the desktop that could be blocking the ping requests coming in from the laptop.

3. In the laptop, try setting the default gateway as if you haven't done it yet. I assume you'll be able to do that, but if you need further instructions on this let me know I'll try my best.

Ok I hope that was somewhat helpful.

Ciao for now.

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