Network Strangeness

[Infektious]

Hello.

We're have a strange problem with this company PC. In an office in another town a PC has been set up to work as a network drive using an IP address. Every computer in this office seems to be able to map the network drive and access the files properly... except for this one. When this PC attempts to 'ping' or 'tracert' the IP it immediately times out. When we attempt to map the drive (Or create a shortcut directly) it says that it 'cannot be found'. We've tried disabling firewalls, Anti-virus, spyware scanners and all sorts of things but no matter what we do it always times out from the start. We've set it up exactly as the others have been set up but still no go. Anyone have any idea of what might be blocking this computer from accessing said Network IP?

For reference:

Windows XP Pro SP2

Pent 4 2.26 GHz

1.00 GB RAM

3Com Etherlink XL 10/100 PCI NIC

Thanks in advance for any help you might be able to offer.

-Terry AKA Infektious

[tjet]

Hello.

We're have a strange problem with this company PC. In an office in another town a PC has been set up to work as a network drive using an IP address. Every computer in this office seems to be able to map the network drive and access the files properly... except for this one. When this PC attempts to 'ping' or 'tracert' the IP it immediately times out. When we attempt to map the drive (Or create a shortcut directly) it says that it 'cannot be found'. We've tried disabling firewalls, Anti-virus, spyware scanners and all sorts of things but no matter what we do it always times out from the start. We've set it up exactly as the others have been set up but still no go. Anyone have any idea of what might be blocking this computer from accessing said Network IP?

For reference:

Windows XP Pro SP2

Pent 4 2.26 GHz

1.00 GB RAM

3Com Etherlink XL 10/100 PCI NIC

Thanks in advance for any help you might be able to offer.

-Terry AKA Infektious

1. Use the Ping or PathPing command-line tools to test basic connectivity. Use Ping to isolate network hardware problems and incompatible configurations. Use PathPing to detect packet loss over multiple-hop trips.

To watch Ping statistics, use the ping -t command. To see statistics and continue, press CTRL+BREAK. To stop, press CTRL+C. If you detect lost packets in the statistics output, it indicates networking problems up to Open Systems Interconnection (OSI) layer 3 (IP-level connectivity).

If the remote system that you ping is across a high-delay link, such as a satellite link, responses may take longer. Use the -w (wait) switch to specify a longer time-out.

2. Check the event logs for network-card-related entries or connectivity-related entries.

For more information, click the following article number to view the article in the Microsoft Knowledge Base:

308427 (http://support.microsoft.com/kb/308427/) How to view and manage event logs in Event Viewer in Windows XP

3. Check whether the network adapter is on the Microsoft Hardware Compatibility List (HCL). To see the HCL, visit the following Microsoft Web site:

http://winqual.microsoft.com/HCL/Default.aspx?m=x (http://winqual.microsoft.com/HCL/Default.aspx?m=x)

4. Check other computers that use the same default gateway that are plugged into the same hub or switch. If these computers do not experience network connectivity problems, the problem may be a faulty network adapter on one computer.

If this is the case, update the network adapter driver to the latest version.

5. Contact the vendor of each motherboard and update the BIOS of the boards. Some network adapters and motherboards or BIOS versions are incompatible. Obtain the latest version from the vendor's Web site or contact your hardware vendor.

6. Check the network adapter and uplink hardware (hub or switch) for common settings. Make sure that all complementing network resources (network adapter, hub, and switch) are set to the same speed and duplex level. If the media type is set to autosense, autosensing, or autodetect, or "Auto Select," make sure that all components are autosensing correctly.

On some switches, a duplex setting of Auto may cause it to use half-duplex. You may have to force it to use full-duplex.

Reset the switch, restart the client, and test the connectivity.

Put the client and the server on a passive hub. If communication resumes, the problem may be caused by an incorrect network switch configuration.

For more information about how to configure the devices, contact your hardware vendor.

7. Manually set the network adapter of the computer that has connectivity problems to half-duplex and a lower speed.

Connect the system to a switch that is configured to half-duplex and 10-Mbps, or use a 10-Mbps hub, to see whether connection can be established at a lower transmission speed.

To increase performance, increase the speed settings manually to 100 Mbps, and then restart the computers. Test for network connectivity loss, increase the setting to full-duplex, and then restart the computers. If network loss occurs, reduce the duplex setting and the speed to the previous settings.

8. Swap the network cable between the failing system and the hub or switch.

9. Replace the network adapter with a network adapter that has been tested and proven reliable. To do this, follow these steps: a. Remove the network adapter diagnostics program.

b. Remove the network adapter in Network properties.

c. Install the new network adapter.

10. Run Network Monitor at the same time on both ends of the network connection. After you filter the traces on the addresses of the two systems, compare both traces to see whether you can see the same traffic.

Use TCP Retransmit, the Network Monitor Experts tool, to detect TCP retransmissions. To do this, follow these steps: a. Start Network Monitor.

b. On the Tools menu, click Experts, and then click TCP Retransmit in the navigation pane.

c. Click Add to Runlist.

d. Click Run Experts.

If frames are missing in one of the traces, check all intermediate cabling, hubs, switches, and routers for hardware or configuration errors.

In Network Monitor, view the Capture Statistics summary frame. This frame is the last frame of the trace. If it contains a value other than 0 in the following statistic counters, the connectivity problem may be caused by a hardware or configuration problem:

STATS: MAC CRC Errors = 0

STATS: MAC Frames Dropped due to HardWare Errors = 0

Network switches and server network adapters have to have the duplex settings matched for communication to function correctly. Both must be set to full-duplex or half-duplex. They cannot be mismatched.

The computers on a local area network (LAN) typically share a common full-duplex network medium. This configuration permits two computers to transmit data at the same time.

Connectivity problems may occur if either of the following conditions is true: • The computer was moved to a new Ethernet switch port that automatically senses network speed. However, the computer's network adapter is configured to force full-duplex communication with a static network transfer speed setting (10 Mbps, 100 Mbps, or 1 gigabit per second [Gbps]).

• Both the Ethernet switch port and the computer's network adapter are configured to force 100-Mbps or 1-Gbps full-duplex communication. However, the Ethernet switch or the network adapter may not be able to communicate at that rate or may not be able to use full-duplex transmissions.

You can improve network performance in an Ethernet LAN environment by using full-duplex hardware. This configuration permits two-way communication between networked devices. Without full-duplex hardware, information is sent one way and then sent the other way. Packets frequently collide on the network in a half-duplex hardware configuration, and every time a collision occurs, the packets that collided must be resent. This creates even more traffic that can decrease network performance.

With full-duplex, transmit and receive paths are separate. Therefore, you can transmit and receive at the same time, and collisions are prevented. Because of the increased throughput and lack of collisions, full-duplex is more susceptible to bad cable terminations or to cable attenuation that exceeds recommended limits. This can generate data retransmissions that become sufficient to degrade performance.

[Infektious]

Wow... thank you very much for that reply. =) I've printed it out to use as reference for a later date. Unfortunately none of it solved my problem. The pathping command showed this computer and then everything after it timed out. Same for all the other commands you suggested. I even changed the duplex settings to no avail. What we find strange is that I can ping anything else except this one specific IP yet everyone else on the network can ping it just fine... and we all use the same hub/switch.

I checked driver version and it's all up to date. I checked the HCL you mentioned and it says this NIC card was designed specifically for WinXP. I'm just at a total loss here... I've never had a problem where I could ping anything in the world except one specific IP addy.

I'm half tempted to ask IT for a new NIC card and see if that does anything... Is there possibly anything else that could cause this?

[tjet]

Have you rechecked the permissions on the file server?

It doesn't sound like it replies when this machine goes looking.

[Infektious]

Permissions have been checked, yes. What's odd is that I can ping anything anywhere else. Doing further investigation with the pathping command you suggested I've found a specific IP address that eats all the packets and it appears to be something on our local network. When the IT guy gets back from lunch I'm going to have him look at it and see what it is. Apparently he didn't look at the switch/hub like he said he did because this IP is the first hop after my computer which I can only logically assume is the switch/hub... but I could be wrong.

[Rich]

Is this address a static IP or a DHCP address? If it is static do you have the correct subnet and gateway address? From the machine having the issue are you able to ping the gateway address? also if your thinking it could be the network card I would check the back of the PC and see if there is even a link light. Also this problem could be a physical issue with the Jack, the ethernet wire, the port on the switch its self, or a cut wire in a wall... it also could have been a software change on the switch its self that set that one port to a different address or vlan... Do you have access to this machine or have someone in that office that you can talk thru checking these out?

-Rich

[Infektious]

I forgot to post that we found a resolution. I don't recall exact what it was but I know it involved changing the IP address of this computer. IT fixed it while I was out of the office and in the field so I don't know exactly what they did.