Sporadic internet connection problem

[esuckq]

Hi all,

Disclaimer: I don't know what I'm doing, so let's keep it simple!

Right: problem is that I can't access some websites, whilst others work fine. Specifically nationalrail.com and prototypegame.com are two unrelated sites that don't load. Status is either "waiting for ...", or "done", while the tab says "connecting". I can ping both of these sites successfully in the cmd box, I can also ping my default gateway. Sites I cannot ping (request timed out) or access include thetrainline.com and microsoft.com!

I'm running Windows 7 Home Premium 64-bit, IE8 and Firefox 3.6. The problem is the same with both browsers.

Things I've tried (in roughly this order):

Running AVG and AdAware scans
Restarting my modem/router
Restarting my computer (multiple times!)
Disabling Windows Firewall
Uninstalling AVG and AdAware
Running CCleaner to get rid of all temporary files, cookies etc.
Cleaning up the registry with CCleaner
Flushing DNS
Renewing IP address
Disabling TCP Windows scaling
Swapping my ADSL filter
Pulling my hair out
Crying
Self harm

If anybody can shed any light on this, you may save my sanity...


Thanks

 

[GhislainG]

To start with, not all sites allow ICMP traffic. The fact that you can't ping or traceroute a site doesn't imply that there's a problem with it.

Have you tried using a different DNS?

 

[eibgrad]

When you ping those sites successfully but otherwise won't load in your browser, do they by any chance always report IP address of 127.0.0.1?

 

[esuckq]

Thanks for your replies GhislainG and eibgrad.

GhislainG: I've now tried using the Google public DNS (8.8.8.8), but the problem's still the same- I assume this is what you meant?

eibgrad: When I ping sites I don't always get an IP address of 127.0.0.1

Oh yea, I've also tried loading safe mode with networking- but still no luck.

Any other ideas?

Thanks

 

[GhislainG]

If using a public DNS, all external host names should be resolved properly. Your answer to eibgrad proves that something is wrong at your end. It definitely isn't normal to sometimes get IP address 127.0.0.1 when pinging any host other than localhost.

 

[eibgrad]

wrt 127.0.0.1 (locahost)

Sometimes anti-virus and anti-malware software (and maybe even malware itself) will muck w/ your hosts file and map domain names to 127.0.0.1. That prevents you from accessing those websites since 127.0.0.1 is your machine! So obviously it can't load.

c:\windows\system32\drivers\etc\hosts

 

[esuckq]

Just to clarify, I never get IP address 127.0.0.1 when pinging any host (other than localhost). But still, I agree it seems likely something is wrong at my end...

 

[GhislainG]

Do have that issue with any browser, e.g., Firefox, Chrome and IE?

 

[esuckq]

Yep, I've tried all three of those and all have the same problem...

 

[GhislainG]

If you have other PCs, do they have the same issue?

 

[esuckq]

Yea I have another one on my home network. Both have roughly the same setup (win7 etc.) and connect throught the same modem/router. Both have the same problem...

 

[GhislainG]

Then the problem should either be with your router or your ISP.

 

[esuckq]

Thanks for you help with this GhislainG...

I've reset my router and gone though the auto-setup procedure and the problem's still there. I really don't know what I'm doing when it comes to playing with router settings so do you have any ideas for what to change?

My ISP is AOL and I have a cheap D-link modem/router that came free with the internet. The only thing I've tried is unticking the Enable Firewall box, but the problem's the same.

 

[GhislainG]

All you can do is contact AOL and have them help you diagnose the cause of your issue. I don't think that AOL is like your average ISP.

 

[esuckq]

Yea I was reluctant to go with AOL, but they were the cheapest for what I needed... now to see how their customer service goes!

Thanks again for the help.

 

[esuckq]

After a week or so of pulling my hair out, some random fiddling finally worked- and I didn't even need to contact AOL!

Changed my MTU setting from 1450 to 1000. Just a guess, but it paid off!!! Now to find out why...