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Hi guys - A while back my workstation started doing something rather strange.

Specs as follows according to Everest, if it helps.

OS is XP Pro SP2
MB is Acer E91M with a P4 3.2ghz 540J

At first login the PC would tell me I had a network error - the message varied between "Limited or No Connectivity" to "Network cable unplugged". After a random amount of time a connection would suddenly be established. (Random as in the shortest time I had to wait was around 60 seconds and the longest 2 hours) Restarting didn't solve the problem.

Once the connection was re-established it wouldn't drop at all even if I did a cold boot. The problem was only at 1st login.
My first guess was that the on-board adapter was damaged, so disabled it and replaced with a seperate NIC but with no luck. Also tried different network points and cables.
Today for the first time it started dropping connection at random during the course of the day as well.

Has anybody had similar experiences? I'm starting to think it's a software issue and not hardware but before I start doing a full re-installation I thought I'd pick some brains.


thanks for any help you can provide!

http://support.microsoft.com/kb/910389

Note particularly: "Allow the computer to turn off this device to save power
If the network adapter supports this option, it is available on the Power Management tab of the network adapter properties dialog box. To resolve this issue, disable this option on the Power Management tab. For more information about how to disable this power management option, click the following article number to view the article in the Microsoft Knowledge Base:
811595 (http://support.microsoft.com/kb/811595/) "A network cable has been unplugged" message appears at seemingly random intervals"

Thanks - Have disabled "save power" function on on-board interface. The NIC doesn't support that function.
I'll have to see in the morning what the results are, and will post then.

For some reason I cannot connect to Microsoft Support but will keep on trying.

Thanks once again.

To test/debug what might really be going on here requires a brief overview on how a computer attains its IP address.
There are different methods possible for a computer to attain an IP address. One of the most common follows a protocol called DHCP. It stands for "Dynamic Host Configuration Protocol". In a simplified view of the process, your computer "requests" an IP address from a DHCP server. The DHCP server grants the request and assigns it an IP address. Note, with this method

• The requesting computer is not guaranteed the same IP address everytime. The choice of IP address is up to the DHCP server which can change it if it feels like it.
• If your computer sits behind a router in your own Local Area Net (LAN) there are two DHCP servers involved
• Computers on your LAN are typically configured to use your router as a DHCP server.(These are all you LAN IP addresses)
• Your router is typically configured to request its IP address from a DHCP server at your ISP (This is your one public IP address)

In reality, the DHCP protocol gets a bit more involved.

• The client computer "requests" an IP address
• The server grants it "a lease" to an IP address. The lease time is the amount of time the client is allowed to use the IP adress granted. Note the IP address granted is not guaranteed to never change even while the client stays up and running.
• When half-the-lease-time has expired, the client must start issuing "renew" requests asking the server to renew its least.
• Anytime before lease expiration, the server may choose assign a new lease time for the IP address or deny the renew request in which case it would typically follow it with a new lease on a new IP address.

just fyi: As i recall the minimum lease time is 8 hours which, for this case, mean a client would start trying to renew its lease as early as every 4 hours.. So theoretically, this method can change your IP address every 4 hours!

To troubleshoot your problem, suggest you understand:

• Is the problem with the ISP assigning the IP to the router?
• Is the problem with your router assigning the IP to your LAN devices?
• Understanding why a IP lease renew request is being denied (if that's the case) and for how long it's being denied. It shouldn't be a problem if it's denied but immediately granted a new lease to a new IP (unless for example maybe the computer who was denied doesn't handle the new IP reassignment very well or so quickly)

To resolve these, you might want to:

1. Test without using a router. Only one computer and one DHCP server in that case
2. Test with mutliple computers going through the router. Some routers will log the DHCP release/renew events which you can read to better undersand what's going ont
3. Go through you router documentation as they often have several options to see what is happening
   • Logging DHCP events
   • Display router current status including what it believes to be the current IP assignment for each computer
   • They provide functions you can use to release/renew IP addresses when you want to
4. Use the ipconfig from a command window on your computer to release/renew IP addresses with the router ipconfig /release or ipconfig /renew
5. Add a "network sniffer" to monitor your LAN traffic and capture and see the DHCP commands between your computers and the router to better understand what might really be going on

Hello Creamy_Goodness,

Definitely read and try what LookinAround has posted. Good job LookinAround, I copied all that down and put it in a text file for later personal use.

The only other thing I can think of would be viruses or spyware. They can do almost anything to computers these days.

I would sugest one of the following anti-viruses
Avast Anti-Virus
AVG Anti-Virus
Avira Anti-Virus
Choose one of those free Anti-Viruses, don't use them all at once. May cause conflicts.

I would recommend Spybot S&D as your Spyware and other malicious software descovery tool.

I would also recommend using CCleaner to remove unneeded files from your computer and to "fix" potential issues in your registry.

Also use ATF_Cleaner to remove unneeded files.

Good Luck

hi everyone im almost having the same problem, i just purchased a wirless netgear wgt624 router and i have a hp vista laptop. i also have an arris touchtone comcast dsl modem. my problem is that i can connect to the internet wirelessly thought the router. but i can not connect on the internet on my desktop. i would like to get the internet goin at the same time both through the router. i have tried to insert an e cable from the router directly to the computer but i get limited or no connectivity. and its not the cable bcuz i swapped out with another e cable and the same result occurs. plz help

Hi djfastlane1

I'm sure you'll be able to get some help. However, you should start by reviewing some Guidelines AND starting a new thread which addresses your problem and put it in the correct forum (for your specific case, ie. Mobile Computing)

Be sure to give more specifics about your hp vista laptop (like make/model and exactly which version of vista). It would also help if you found the tag on your cable modem and stated its exact make/model number as well.

There are many variables involved in fixing a problem. Always start by indicating your hardware and software specifics for what;s involved. (e.g. There are several different versions of Vista. Knowing which version can make a difference)

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get a command prompt (run->cmd) and enter
ipconfig /all
copy and paste the results in your follow.

'limited connectivity' usually means your system did not find the DHCP service
and therefore took a default 169.x.x.x address.

If you see that, then go to your NIC and be sure to set DHCP for both the IP & DNS addresses.

what is a NIC? and how do i this?

NIC stands for Network Interface Card....

Go to RUN and type in "cmd" press enter

Type in ipconfig /all and press enter

Various information will be displayed

We need to know what Ip address, subnet mask, default gateway you have been assigned and wether you have DHCP enabled.... oh and your DNS details would be helpfull too.

ok i did all of that and yes dns is enabled. now wat?

DNS or DHCP?

sorri bout that DHCP

sounds like you need to clear your winsocket try what I have posted below.

Open a Command Prompt window
1. Start>Run>Type cmd and click ok you will get a black box.
2. Type netsh int ip reset resetlog.txt and press Enter make sure to put the spaces. The original prompt will reappear.
3. Now type netsh winsock reset catalog and press Enter
4. type exit press Enter and reboot the laptop.

Let me know if this solve the problem.

if im doin all of this on my laptop, or am i? but if im doin this on my laptop then how does it help my connection on my desktop?

lol this is a normal thing I post I forgot to change it to desktop

ok i did wat u said and nothing happened.

sorry can you give more information. Nothing happen when you entered the commands in the black window or after you rebooted you still get the same problem

after i rebooted i had the same problem

I want to see if you dont have a malware that is blocking your internet

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