Question about Dell Latitude C400 Notebook

1 Answer

Ethernet port not "active"

My Dell Latitude C400 LAn/Ethernet port doesn't appear to be functioning. There are no link /data lights when an Ethernet cable is plugged in. When cable is unplugged it does show that a network cable is unplugged message. I checked the device manager and it shows that the 3Com 3C920( 3C905C-TX) is working properly. I even installed fresh drivers for the 3Com 3C920( 3C905C-TX) . Still not picking up connection.
Can it be a bad LAN/Ethernet port??
Can I get a cheap mini wireless card to bypass LAN/Ethernet??

Posted by on

  • 8 more comments 
  • arosest1 Apr 22, 2009

    Yes, I have tried a brand spankin new LAN cable . Still nothing.

    I will try the BIOS option later. Is it listed under "On board LAN"?

  • arosest1 Apr 27, 2009

    Hi Jerry and thanks for the help. LAN is dead. LAN is enabled in BIOS. Strange that when LAN is unplugged system notices LAN cable is unplugged.Then...when I tried the phone line connection I received a SM56 codec error. I fixed that with a DL of a new driver but it still can not dial out. Seems COM port 3 is closed and I can not query modem. I tried to assign another COM port but same . Is there a PCI slot card that will work with my PC and then I can connect a phone line and dial my ISP?

  • arosest1 Apr 27, 2009

    Sorry, I may have mis spoken. I DL drivers for the SM56 speakerphone modem , NOT the NIC. Couldn't find SM56 drivers , Motorola shows no longer available,but did find compatible drivers and I now no longer receive the SM56 incompatible codec error.Now I get a COM port error when quering modem. As for the NIC....all appears to be OK in device manager and BIOS. Shows LAN cable unplugged and balloon message goes away when LAN cable plugged in but no link lights on port, can't ping...shows "media not connected" error. This was given to me by a friend that bought a new one. He stated it did work but not sure when the last time was.

  • arosest1 Apr 27, 2009

    Hi again,

    I did check Dell and put in the service tag and found appropriate modem and DL those drivers, uninstalled/reinstalled...rebooted and new HW wizaed came up and installed modem....NOT the SM56 but off hand I don't have the exact modem info in front of me. Installed without issue but when I try to dial out I get a COM error....that the COMport 3 is closed. Tried to assign to a higher COM port but same. IT WILL NOT DIAL OUT. I believe the LAN could be shot and I am not replacing a MB for a Dell D400. Not worth it. A PCMIA card with phone connection is cheapest..........correct??

  • arosest1 Apr 27, 2009


    Thanks for all your help. I will be sure to use this site again in the future should I run into any technical issues that are beyond my grasp. Hopefully you'll be the one answering !


  • Jerry May 11, 2010

    You can get both a PCMCIA card for both modem and ethernet. I'm not sure which route you're going to go to connect to the internet, but obviously if you have high speed internet, your best bet would be to do a PCMCIA ethernet card. Try this website, I use them almost exclusively to price, etc:

    You can get a PCMCIA for a gig connection for around $15.00, the Netgear GA511 would be a decent one. Unless your router is a specific brand, I would also stick to same brand for an easier configuration. Good luck and let me know how it turns out.

  • Jerry May 11, 2010

    One thing I'm confused about, you mention you have SM56 Speakerphone modem, however, the drivers listed that came shipped for that particular laptop, don't show that model modem. Look, I'm sure you already did:

    Possible to uninstall and install one of the supported modems on that page? Even if the drivers is a bit older.

  • Jerry May 11, 2010

    There are no internal pci slots like you would have on a desktop. However, your system does have a PCMCIA slot. The dell website lists the following devices as being compatible with your system:

    You said you had installed fresh drivers for your onboard NIC, however, the drivers I find for your system, the lastest listed is 2003. Can you give me the version of the driver and date? I'd like to look elsewhere for the drivers. A lot of times, drives dont' have to come specifically from the hardware vendor. It is strange how your onboard NIC is behaving. Another thing I never asked is, has the NIC ever worked? Or is this a more recent problem?

  • Jerry May 11, 2010

    Yes, it is found under "On-board LAN." But it doesn't sound like that's your problem. You probably would see it in "Device Manager" disabled. Your next option maybe as you said, purchasing a wireless adapter. I would stick to the same brand as your wireless router. If you need help deciphering which type, let me know. Pretty much, all of the major brands are good, but again, for simplicity, stick with the same brand as router. Also, if you have a G router, ensure your wireless adapter also supports G or higher.

  • Jerry May 11, 2010

    Have you tried using a different ethernet cable? Sometimes cables do go/are bad.



1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • Dell Master
  • 4,806 Answers

Hi there.
Restart the PC and go into the bios to make sure the on-board LAN is enabled, if it is try as jery says and try another ethernet cable.

Post back please and good luck

Posted on Apr 21, 2009

  • Lee Hodgson
    Lee Hodgson Apr 22, 2009

    yes it will be listed under on-board LAN

    good luck



1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

I cant format my C400 with a pen drive

If you're tryng to format the HDD on a Dell latitude C400 (or install an OS), this thing will not boot to any USB devices (flash drives, pen drives, external USB cd-rom drives, etc.) - just ain't gonna happen since the BIOS doesn't support such boot devices. The only thing it'll boot to is (1) docking station, and (2) a Media Bay optical drive.

Sep 01, 2011 | Dell Latitude C400 Notebook

2 Answers

I'm bought dell latitude E6400 inbuld modem. so how can use internet on it.


You can use the ethernet port or the wireless LAN of your laptop to connect to the internet. You can refer to the link below for the specification of your laptop

Also refer to the link below for the location of the Ethernet LAN port of your laptop.

Mar 30, 2011 | Dell Latitude E6400 Notebook

1 Answer

I am using the Dell Latitude D620, When i am connecting this machine on network I am getting 100 MBPS connectivity, but when i am connecting other machine to the same network port I am getting 1GBPS...

Hi Ajay,

The LAN (wired network) connectivity speed/data rate depends upon the networking hardware (Laptop Ethernet Cards, Switch, Router etc.).
To get 1Gbps connectivity you must have 1Gbps ethernet (LAN) card in the laptops. As Dell Latitude D620 has 1Gbps card, the problem could be with the switch or router, which may be having 100Mbps and 1Gbps ports, depending upon the equipment you are using and it is recommended that you check out the its full specification. If you connect laptop to 100Mbps port you can only get 100Mbps speed. To get full speed, it is required to have 1Gbps support at both ends.

Dont forget to rate the solution if it helps!!

Dec 03, 2010 | Dell Ethernet Card Network Adapter

2 Answers

The USB port on my DELL Latitude C400 does not recognize the mouse

try to use otehr usb ports on your computer. check if the light on the bottom of the mouse lit up. open device manager. under mouse - delete otehr mouse components then restart computer.

Mar 08, 2010 | Dell Latitude C400 Notebook

1 Answer

The usb of my dell latitude c400 notebook is malfunctioning

Unfortunately, I have seen this many times. One of the major problems with the C400 model was the USB port failing. I have had many of them replaced under warranty, and I have repaired some. The USB port breaks loose from the mother board and stops working. It is possible to SOMETIMES disassemble the laptop enough to get to the port and re-solder the USB port connections. But is is a slow process for experienced people. And it does not work all of the time. i know that this is not the answer that you wanted.

Good luck with it.

~ Spoem

Mar 18, 2009 | Dell Latitude C400 Notebook

1 Answer

My dell computer suddenly is not connecting to the internet and is showing "network cable unplugged" error

  1. start the troubleshooting process by making sure that everything (routers,switches, hubs, modems, and computers) is firmlyplugged in.
  2. If your computer is on and the other end of the Ethernet cable isconnected to a network device, the link or activity LED should light.If the light remains dark after you plug in the cable, replace thecable. If replacing the cable gives the same result (no green light), then go to the next step.
  3. Once you’ve eliminated cabling as a source of the problem, it’s time tolook to your computer. Start by making sure that your computer is able toaccess your Ethernet card. A good tool for doing this, and subsequentnetwork troubleshooting, is the command prompt.
  4. Select Start, All Programs, Accessories, and then Command Prompt. When the Command Prompt window opens, type ipconfig –alland press ENTER. Various lines of information will display, dependingon how your system is configured. Look for a section labeled EthernetAdapter Local Area Connection. This section should include a linelabeled Description, which should be a description of your Ethernetcard. If you see it, then your computer knows about your Ethernet cardand has successfully loaded the necessary drivers. If the Descriptionline is blank or missing, you will need to reinstall the drivers foryour Ethernet card.
  5. Your Ethernet card doesn’t detect a connection to the Ethernet cable. Open a command prompt, type ipconfig –all,and press ENTER. If the section that starts with Ethernet adapter LocalArea Connection contains a line labeled Media, with a status of MediaDisconnected, then your computer is unable to detect that a link hasbeen made from your Ethernet card through the Ethernet cable to anothernetwork device, such as your computer or router. Recheck the cabling.Use a known good cable to connect your computer to a known good networkdevice and then perform the check again. If the status is still MediaDisconnected, and you are sure that the cable and the network devicethe cable connects to are good, then you may have a bad Ethernet card.Reinstall the Ethernet card. If the problem continues, you may need toreplace the card.
  6. Other things to check:
  7. Bad connection, bad cable, or wrong cable. The ports on arouter, hub, switch, wireless access point, and print server can, likeany other device, go bad. However, the most common problem is not a badport but a bad or loose connection, a bad Ethernet cable, or the wrongtype of cable. Refer to the Cabling section above, to eliminate thesepossibilities.
  8. Wrong port. One possible cause of Ethernet port problems isusing the wrong port on a network device. For example, routers have WAN(wide-area network) and LAN ports. These ports accept the same Ethernetcabling but are not interchangeable. The same is true of hubs andswitches that have uplink ports, which are specially wired LAN portsthat allow easy cascading of multiple hubs and switches. In some cases,the uplink port is also a normal LAN port controlled by a switch on thedevice. If you’re using the uplink port as a normal LAN port, make surethe device is configured properly for this type of use.

    If aport doesn’t appear to be working, you can use the link light toconfirm it. Port link lights should always be lit when a good cable isconnected between the port and another working network device. If youuse known good cable and a known good network device to test the portbut the link light isn’t lit, you may have a bad port. You can eitherreplace the network device, or in the case of a hub/switch, add a hubor switch to gain more LAN ports.
  9. You cannot connect to other computers or router/Internet. Whenother computers in your LAN can connect to each other, as well as tothe Internet or other services, and your computer cannot, this may bean indication that your computer did not receive an IP (InternetProtocol) assignment when you booted.
  10. Open a command prompt, type ipconfig –all, and press ENTER. Inthe section labeled Ethernet adapter Local Area Connection, look forthe line labeled IP. If it starts with 169, you have a self-assignedIP, which indicates that your computer was not able to acquire an IPassignment from the DHCP (Dynamic Host Configuration Protocol) server.

    Test your access to the DHCP server by using the ping command. Open a command prompt and type pingfollowed by the IP address of the DHCP server. Your DHCP server isprobably the same as your router. For example, if your router’s IP is192.168.1.1, then type ping and press ENTER. Youshould see four lines of text, starting with Reply From 32, followed by time values that indicate how much time elapsedbetween the ping command and the router’s response. If you see fourlines that say Request Timed Out, then your computer cannot reach yourrouter/DHCP server.

    Make sure the router is plugged in,turned on, and properly configured to provide DHCP services.
These are just a few things to try to help figure out if it is your cable, ethernet card, router, or some other problem.

Jan 19, 2009 | Dell Ethernet Card Network Adapter

1 Answer

What do I need to go onto the internet wirelessly

Reinstall the W-Lan drivers..
download them from the following link

best regards,

Dec 04, 2008 | Dell Latitude C400 Notebook

1 Answer

Cant get on internet via wireless or wired connection.

use the lan connection to get online, then once prob clears you should be all set, otherwise back up your data and a fresh install always does the trick

Nov 20, 2008 | Dell Latitude C400 Notebook

Not finding what you are looking for?
Dell Latitude C400 Notebook Logo

781 people viewed this question

Ask a Question

Usually answered in minutes!

Top Dell Computers & Internet Experts

Les Dickinson
Les Dickinson

Level 3 Expert

18394 Answers

Doctor PC
Doctor PC

Level 3 Expert

7733 Answers

mukhtar21 shaikh
mukhtar21 shaikh

Level 3 Expert

2017 Answers

Are you a Dell Computer and Internet Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides