No internet

My onboard Intel 82566DM-2 now and then refused to make internet connection. The last few days it almost stopped al all. Sometimes after 10 restarts it worked again. So I installed a Realtek 8169 network adapter which worked the first time and then gave the same problem: no internet connection.
All other computers/laptops in the network have no connection problems at all. I switched cabled to no avail.
Anyone a suggestion where to look for a solution?

Have you tried a different port on your router/switch?

Checked for viruses or malware? Swapped cat-5 cables? Ensured that the cable is plugged in tightly?

Yes. I switched ports and cables, connected directly to router.

If I start computer I get no connection, if I then switch cable from the onboard networkadapter to the Realtek network card I do get a connection (and vice versa!). So the one I start with does not work and switching makes it work....

Assuming you have XP, when you have no connection, try hitting the Start button, choose Run, then in the resulting box type CMD and a DOS box will appear. Tyoe "IPCONFIG /FLUSHDNS", then hit enter. Then type "IPCONFIG /RELEASE" , hit enter, then type "IPCONFIG /RENEW" all without the quotation marks. This should flush the Dynamic Naming system of old crap, release and renew your IP addy. It doesn't matter if you use all caps or lower case letters.

Thank you, I will do next time (I use Windows 7, but that makes no difference.)

Guts3d,

Your solution works, thank you. Do I have to do this every time I logon (I tried it several times and had to do it each time)?
Was is the cause of this behaviour?

Unlikely, it sounds like you are infected.
Once should be enough.
What antivirus do you have?
What malware cleaner have you used?

I use Microsoft Security Essentials and Spybot Search & Destroy.
Both found no viruses / malware.
Try another one?

You can certainly try Malwarebytes
Install it update it and be sure you do a full scan.

Full scan done, no problems

Suggestion; go to control panel and create a new account ( limited, of course! ) and see if that has any problems hitting the net. If not, it might just be a corrupt account. If it has problems, you might want to boot into safe mode and scan for viruses.

Another account, same problem.

Pretty much whats left is a format and reinstall.

Well, that is of course an option. What could be the cause of this behavior?

corrupted reg key maybe.
Quite often in cases like this I will just use a
small drive and do a fresh load of windows
and see if the same problem occurs

Thanks for your help. Could a test with Ubuntu be worth a trial?

I think malware is still a good bet. Spybot and Malwarebytes just can't deal with most rootkits. I sorta like Microsoft Security Essentials, but my perception is that it is beginning to slip off the curve.

Personally, what I would do is download and run Kasperky's TDSSKiller, and if it finds any infections, remove them, reboot and run it again.

Secondly, I would download and run Combofix. Read the guide before you run it. Afterward, re-scan with MBAM and Spybot. Despite the disclaimers, Combofix is generally safe to use, but you should re-run Spybot's immunization feature after Combofix, because it will probably delete your Hosts file.

Ubuntu is certainly worth a look, but I'd run it from a LiveCD to experiment with, rather than actually installing it, for a test drive. I believe Ubuntu is the most polished desktop Linux distribution around, but don't expect it to be as easy to set up and get working with your hardware as Windows.

Thanks for the info, will do tomorrow...

No malware detected. It does not matter whch adapter I use, the onboard or the additional Realtek, both give the same problems.

I recall having a silly issue long ago with connectivity and the solution was manually uninstalling all networking protocols and then manually uninstalling the device through device manager and rebooting before the system could detect the device again. Then once you reboot do not let it install the devices automatically and do an install of them by adding a new device and manually selecting the .dll files from new install files/folders that you download from another machine.

Stupid? Yes. Too much work? Most likely. Will it work? It's always worked for me.

Always worth a try!

So, did you try test running ubuntu via live cd/live usb and see if you have a working network connection? What happened with that?

Tried it (using it now) and works without a problem. So it is a Windows 7 problem.

What I do not understand is that if I look in my router my PC has IP-address 10.0.0.191, but if I look at the details of the connection my adapter has IP-address 10.0.0.199

Shouldn't that be the same?

Statically set the DNS on the network card.You can log into your router and get the DNS srvers assigned by your iSP and then hardcode them in the network card.
Windows 7 and vista sometimes have issues with DNS and routers. They both query Microsoft every so often and if they cannot resolve the domain name they show a limited connection.

Changed it, but still no connection.

What make and model router? Have you checked that it is in fact windows 7 compatible?
Some routers are not compatible without a firmware update

It's an Alcatel Speedtouch 510 from 2003.....

Back up your data, and do a format and reload.

I am not 100% sure about the Alcatel Speedtouch 510 but looking on Google i really dont think it is windows 7 compatible.If it is provided by your ISP why not request a change to one that is windows 7 compatible?
What firmware version is the modem running?

The firmware version is 4.0.2.0.0, but the most recent firmware is from 2005 or thereabout.

Have you tried to uncheck TCP/IP V6 in the properties of the network card and see if that helps?

Tried it, but didn't help.

Did you have to purchase that modem or was it provided by the ISP?
If you have a spare router and know all the logon info you could always try setting it (the speedstream 510) to bridge mode and connecting a router.

The router was free when I started with ADSL. I'll try to get/borrow another router to test it. I have all settings information.

Quote:

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Originally Posted by panhead

Well, that is of course an option. What could be the cause of this behavior?

---

Well, that is an excellent question, but difficult to answer with precision. Third party firewall, when uninstalled, often break TCP/IP. So, if you once ran Norton 360, Norton Internet Security, AVG 2011, etc. that could be a cause. And frankly, even for those of us in the business, it's possible to overlook some of the changes to network settings that can block Internet access, especially when you're tired or frustrated. Never hurts to double check and make sure you don't have any hijacked settings for a proxy server, or DNS servers.

And, sometimes, stuff just gets corrupted or damaged. I would always suggest running System File Checker before a format and clean installtion, and you might try resetting Winsock. Per MS KB 936211:

To do this, follow these steps:
Click Start, and in Start Search, type cmd.
Right-click the cmd entry that appears in the search results, and then click Run as administrator. If you are prompted for an administrator password or for a confirmation, type the password, or click Continue.
At the command prompt, type the following, and then press ENTER:
netsh winsock reset
Then, you should see the following message:
Successfully reset the Winsock Catalog. You must restart the computer in order to complete the reset.
Restart the computer.
Note If you receive an “Access Denied” error message instead of the message that is mentioned in step 3, the command prompt was not correctly elevated. In this case, close the Command Prompt window, and repeat steps 1 through 3. Make sure that you correctly implement step 2.

If you still don't have a connection, try resetting the Hosts file (rerun immunization afterwards):

Let me fix it myself
To reset the Hosts file back to the default yourself, follow these steps:
Click Start, type drivers in the Start Search box, and then press ENTER.
Click the entry for drivers that is displayed in the search results. The icon next to drivers will be a folder.
A window appears that will display Windows > system32 > drivers in the address bar at the top. Double-click the etc folder.
Locate and right-click the hosts file, and then click Rename.
Type oldhosts, and then press ENTER. If you receive the following error message click Continue:
You need to confirm this operation.
If you are prompted for an administrator password or for a confirmation, type the password, or click Continue.
Restart the computer to make sure that the change takes effect.
Test Internet Explorer.
Check whether the configuration of the Winsock protocol and the HOSTS file is reset. If it is, you are finished with this section. If the Winsock protocol or HOSTS file is not reset, you can contact support.

Thanks for the reply, I will give it a try when I'm home.

slgrieb: I tried resetting the winsock settings and after the restart I had internet access! I'll try it a few more times and let you know.

Well, that didn't last long, only 1 time connection. The second solution (rename hosts file) also no success.