Wired Connection - Strange Behavior

A friend has a 64 bit W7 desktop computer that had not been used in years. I checked it out briefly and told her I'd have to take it home to fully investigate it's problems. When I brought it home and hooked it up to my modem there seemed to be no problems with establishing a solid internet connection.

Nonetheless I ran all the Windows updates, ran a full Malwarebytes scan, cleaned up her msconfig startup and checked it again. It seemed to be fine, connecting effortlessly, so I took it back to her place. It turned back into a pumpkin. Her home page (Google) came up, and she could enter search items and receive suggestions. But she was unable to bring up any pages from the Google results - it would just show a blank page with the little blue circle. We called her ISP and they gave her a free speed upgrade that would take effect on the 1st of June.

June 2nd she called me and told me that nothing had changed. I went back to her place today with an old XP laptop with about a half GB of memory. I used her Ethernet cable and the old laptop worked better than ever. Her tower continued to non-perform bringing up Google results, but not letting her click on them. Her Verizon page would never display.

I brought it back to my house, ran JRT, Adwcleaner, RKill, TDSSKiller and a full MSE scan. Nothing of substance was found, so I have no confidence that it will work any better back at her house.

Any ideas?

Is she behind a NAT?

UsernameIssues said:

Is she behind a NAT?

Network Address Translation? I don't know exactly what that is, how to check for it, or how to fix it if she is. I somehow thought that NAT had something to do with a router. She has no router - just a modem.

If it means anything, I looked at the properties for ipv4 and v6 and they both said to obtain an ip address automatically.

I had written out several questions and things to check - but then it dawned on me that it all hinged on her being behind a NAT (Network Address Translation). So, I wrote over my ramblings with that all to brief question. Sorry.

Here is a link that talks a bit about NATs without going too deep:
Network Address Translation

Here is simple way to tell what your internet facing IP address is:
Address test
(No adverts of junk to infect you.)

I'll post a bit more later.

So....., since she does not have a router she cannot be running behind a NAT. I'm supposed to drop her PC off today and I just wondered if anybody else has any thoughts on the problem. As I said, it's running beautifully here. I've since run a chkdsk, sfc /scannow, Rogue Killer, ESET Online Scanner, a full Windows All-in-one repair and a custom Malwarebytes scan, checking for rootkits. No errors, viruses, integrity violations, etc. I've also installed Firefox and reset Internet Explorer.

DMHolt57 said:

I would first compare the ipconfig /all from the two machines to see if there is an apparent change in the defaults for dns and gateway. Try killing the power to the modem and the pc, start up the modem with no connection to the pc, when all the lights have stopped flashing and it shows connected to isp, then connect a cable and start the pc, it should auto configure if the wlan service starts without problems. You could manually set the dns for the adapter to 8.8.4.4 or 8.8.8.8 these are Google public dns also if no default gateway shows in the ipv4 adapter properties, try inserting the modem address. After a couple reboots it could straighten itself out... strange that it is only her modem, I suspect it could be dns related...

Thanks for the reply. When you say 'it should auto configure if the wlan service starts without problems'...., what does the wlan service have to do with a wired connection? She has no router - just a straight connection between her tower an her modem. And it's not like her connection doesn't work at all. It sort of works.

DMHolt57 said:

...my bad, I meant the wired auto configuration service. Did you look at the dns in the advanced properties of ipv4?

No. You'd asked me to compare the ipconfig /all results obtained using her modem/her tower against the results obtained using her modem/my laptop. When I took her tower back and tested, those results were negligible. Yet once again my laptop (this time a 64 bit Windows 7 Dell) connected flawlessly, while her tower would usually bring up a blank page with the msg 'waiting for verizon.com'. You never said anything to me about going into the connection properties and looking at the ipv4 settings. And I've returned the tower, so I can no longer check.

Verizon IS sending out a new modem - an upgrade from her old Westell, which must be 10 years old. We'll see, but I doubt a new modem will change a thing.

boweasel said:

So....., since she does not have a router she cannot be running behind a NAT.
~~~

It is possible to have a NAT in a modem and the new one probably does.

If you get the chance, please write down the new modem's brand/model info.


While you are there:
You might also want to install TeamViewer
(Run the installer from a USB stick - if need be.)

If the new modem allows multiple computers to connect at the same time, test you ability to connect to her computer via TeamViewer. Even if she can not surf to websites beyond Google's search returns, there is a good chance that TeamViewer will still connect.

See my ramblings about TeamViewer in this post.