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david1300
31st Jan 2013, 00:09
Or so my computer tells me:
http://i46.tinypic.com/ih4cug.jpg

http://i48.tinypic.com/rvdand.jpg

Symptoms are:
1 - some websites just don't load at all
2 - some load partially
3 - others seem to load fine
4 - this pattern is consistent across our whole network - this computer plus one other connected to Netgear Wireless Modem (both hardwired by blue (forget the name) cable); laptop connected to wireless network; 2 iPads connected to wireless newtwork.

Diagnostics done so far:
1 - interenet connection is good (haha - if only this reflected real life. This speed is to the nearest big city server)
http://i47.tinypic.com/qnw5xg.jpg
2 - computers rebooted
3 - modem disconnected and reconnected, including power.
4 - connection to websites checked via iPads through 3G (disconnected from wireless network) and they download OK

What I have done recently (different from daily routine):
1 - Installed and run Malwarebytes (before problem started)
2 - Installed and run Hitman Pro direct from link provided by Milo in other Firewall thread
3 - Tried to install and run ComboFix direct from link provided by Milo in other Firewall thread (after problem started)
4 - Installed Dragon Naturally Speaking 12. Have had some setup problems due to incompatability of analogue headphone/software with my 'onboard' sound card. Apparently will be resolved through using USB headset.

It seems to me that somehow there is a firewall setting in my Wireless Modem (NETGEAR, as supplied by my Internet Service Provider) that 'THEY' have changed. (Just because I'm paranoid doesn't mean that they aren't out to get me).

I've reached the end of my diagnostic & repair skills. Can somone help, please?

Milo, MikeB & others - you're patience with and help to us 'babes in the woods' is greatly appreciated.:ok:

Superpilot
31st Jan 2013, 02:25
Just a note but IE on an XP machine is asking for it as MS are no longer updating or patching it meaning the list of vulnerabilities to exploit will only increase.

For further troubleshooting from one of the machine, launch Start>Run>CMD and in the command line window type: ping 8.8.8.8 -t . This will set up a continuous ping to one of Google's DNS servers. Leave this running, providing outbound pings are not blocked by your router/firewall you should get a continuous reply along with a round trip time like this:

Reply from 8.8.8.8: bytes=32 time=52ms TTL=47

See if there are any "Request timed out" entries in the response over a period of 10-15 minutes. After this period, within the command line window, press CTRL+C you will then get some statistics like this:

Ping statistics for 8.8.8.8:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 52ms, Maximum = 444ms, Average = 154ms

If the above is OK and you get zero loss or something that's less than 2% then there is no packet loss meaning there is no basic connectivity issue.

There is lots you could do here to further troubleshoot and we can try some more things later.

However first of all (long shot) try temporarily specifying an alternative DNS server on one of the computers within TCP/IP settings. Why are we doing this? Well it could be that the first public DNS server your router is hitting is flakey and not responding to all requests to resolve website names all the time. Below is a screenshot.

http://www.home-network-help.com/images/google-public-dns-servers.jpg

Specify the examples shown. Now try browsing checking for a consistent experience.

david1300
31st Jan 2013, 05:33
Superpilot - thanks for the help. I ran the Ping test, but cannot get this part to work:

After this period, within the command line window, press CTRL+C you will then get some statistics like this:

Ping statistics for 8.8.8.8:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 52ms, Maximum = 444ms, Average = 154ms

Pressing CTRL+C does nothing. But I have scanned through the continually scrolling results every few minutes and it all just appears like this:
http://i50.tinypic.com/19mg4y.jpg

I also wanted to try your second suggestion, and my gut feel is that this is on the right track, BUT my computer illeteracy kicked in. I cannot find that Internet Protocol (TCP/IP) Properties dialogue box. I have looked everywhere, but 'THEY' have got it hidden somewhere. I had expected to find it somewhere here,. but no luck:
http://i49.tinypic.com/2m813ef.jpg

Pages only partly load, for example, right now the posting toolbar (Bold, Italics, font colour, etc) won't display, nor will the pictures.

Superpilot
31st Jan 2013, 06:09
OK so you have no packet loss. Based on your last description on the way pages load I would now bet it's not DNS but it's still worth a go...

1.) Control Panel > Network Connections
2.) Right click your LAN or WLAN connection and choose Properties
3.) At the bottom of the list in the centre of the page, select Internet Protocol (TCP/IP) and click Properties

David also turn off all internet connected devices/detach from the network and try browsing the web from each one one at time.

david1300
31st Jan 2013, 11:14
Superpilot, thank you.

I changed the DNS Server settings as per your piccie. Thanks for walking me through where to find it.

Initially disconnected all other devices, rebooted and it is working well now, including from other networked computers, and wireless-connected iPad.

Here is my theory (which may be rubbish, because my wife tells me to stop self-diagnosing and telling the doctor what is wrong with me, and rather just describe the symptoms and let him diagnose).

I think it's a service provider problem. We have had floods all through our state, and I think they have some service issues. I am connecting to other servers at good speeds. I would liken this to the following example: my 'old' route has become flooded and the data was forcing it's way through the flooded creek; we now have a different route so the data is all getting through. This doesn't explain the 'no dropped packets' though.

Oh well, bedtime here, and for now I can sleep easy and say thank you once again, superpilot. I'll check again tomorrow, and through the weekend, and let you know if this is a permanent fix.

Superpilot
31st Jan 2013, 14:49
Just to make sure it is DNS and not some unrelated fluke, have you tried putting the default settings back on one of the PCs?

If it was the DNS fix for sure, you had better tell your ISP that either their DNS servers are FUBAR or the first hop DNS settings on your router are incorrect and need changing as you can surf the net just fine by going directly to Google's DNS servers.

Milo Minderbinder
31st Jan 2013, 15:58
I don't think theres anything unusual here

Its a Netgear modem/router. Put quite simply, they do this. After a few years they go wrong, and DNS resolution breaks down. You find they can resolve some sites but not others. It usually coincides with them running hot.

Sometimes you can get them working again by setting the router defaults and then configuring them, but usually not.
Personally, I'd try a new router

Ancient Observer
31st Jan 2013, 16:55
That's rather a nice story. For those like me who are at best averagely competent with a pc, it is stories like this that educate me.

Thank you to the contributors.

(I wish I'd read it some time ago when my budget netgear (now departed to the land of dead pc kit) was sending me/my pc off looking for the wrong place on the net). If the internet had allowed it, my pings would have been hours long............)

david1300
1st Feb 2013, 01:51
I'm going to continue running as is (new DNS setting) for the next 3 days to be confident of the stability, then I'll reset them and test.

Milo, thanks for your input. I'll keep that in mind.:ok: In my Netgear box was my my old Netgear modem/router, replaced by current one 4 years ago. (No I'm not a hoarder - it does have a symbol showing not to be discarded in rubbish:O:O).

Mike-Bracknell
1st Feb 2013, 09:28
Partial page loading and sites not accessible generally are a pointer either (as Milo says) that your router is on the way out, but can also be:

- the wrong MTU setting on the router (this dictates the packet fragmentation size and can result in retransmits and loss if incorrectly set)
- a routing issue further in the internet

I would suggest, before you replace your router or look at the MTU issue, you ring up your ISP and explain the problem to them, as I saw this issue on a customer here who's ISP had recently initiated an IPv6 programme on their network and had made a config error. (Kingston comms for those of you in the UK)

david1300
7th Feb 2013, 05:47
I reset the router DNS settings 3 days ago, and have had no trouble. I think the problem may have been downstream (or should that be downline) from here. It may have been attributable to infrastructure damage from storms and floods and Service Provider Problems that they weren't publicising too widely, as they were already copping plenty of flack.

Thank you again everyone for your generous and patient help :ok::ok: