Cannot access certain sites

[biostud]

My sister cannot access certain sites from her computer. On the same network her ipad can access them without any problems, so I think that would rule out the ISP.

One of the sites is bbc.co.uk.

When she runs a "ping bbc.co.uk" she gets no reply.

how to fix this?

First I've set her to run a full system scan with

f-secure online scanner

http://www.f-secure.com/en/web/home_global/online-scanner

What will be next step if that doesn't solve the problem?

 

[AnitaPeterson]

You're not alone.

I'm at work today, and we've been having inexplicable problems in connecting to certain sites and servers. The problem seems to come and go, but it became quite annoying in the early afternoon.

Strangely enough, though, some of the sites that are down are big names like Google, Gizmodo, BBC and so on. Meanwhile, Anandtech and a few foreign sites (on European servers and in the Middle East) are OK...

To be honest, my first suspicion was that this was part of a surprise first strike in Syria... How did that quote go? "Communications disruptions can only mean one thing: Invasion."

 

[biostud]

She's had this problem for several months, so I don't think it's Syria related

 

[gevorg]

did you check the hosts file?

any news apps installed recently?

any recent router config changes?

 

[MontyAC]

Has she tried different browsers? Maybe change to the OpenDNS or Google DNS servers.

 

[biostud]

how do you check the host files to see if they're wrong?

all the browsers are the same, and ping command cannot acces the sites either.

 

[lxskllr]

how do you check the host files to see if they're wrong?

https://en.wikipedia.org/wiki/Hosts_file

Make sure the sites you want aren't being redirected to nowhere. The file should be almost empty, but it may have stuff in it if you've used 'immunization' features of anti malware products. If your list is big, and legit, do a search for the domains that aren't working.

Edit:
This is the beginning of my hosts file from Vista. The spybot modifications go on for awhile, but you can see what it's supposed to look like. Bad site redirections get sent to localhost, so they can't be accessed.

# Copyright (c) 1993-2006 Microsoft Corp.
#
# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
#
# This file contains the mappings of IP addresses to host names. Each
# entry should be kept on an individual line. The IP address should
# be placed in the first column followed by the corresponding host name.
# The IP address and the host name should be separated by at least one
# space.
#
# Additionally, comments (such as these) may be inserted on individual
# lines or following the machine name denoted by a '#' symbol.
#
# For example:
#
#      102.54.94.97     rhino.acme.com          # source server
#       38.25.63.10     x.acme.com              # x client host

127.0.0.1       localhost
::1             localhost
# Start of entries inserted by Spybot - Search & Destroy
# This list is Copyright 2000-2008 Safer Networking Limited
127.0.0.1	007guard.com
127.0.0.1	www.007guard.com
127.0.0.1	008i.com
127.0.0.1	008k.com
127.0.0.1	www.008k.com
127.0.0.1	00hq.com
127.0.0.1	www.00hq.com
127.0.0.1	010402.com
127.0.0.1	032439.com
127.0.0.1	www.032439.com
127.0.0.1	100888290cs.com
127.0.0.1	www.100888290cs.com
127.0.0.1	100sexlinks.com
127.0.0.1	www.100sexlinks.com
127.0.0.1	10sek.com
127.0.0.1	www.10sek.com
127.0.0.1	123topsearch.com
127.0.0.1	www.123topsearch.com

 

[gevorg]

edit: see above

 

[Engineer]

Was having trouble connecting to sites a few days ago. The "Isitdownforeveryoneorjustme" site showed that the sites were fine. I finally changed from Google DNS back to Time Warner DNS and they started working.

I wonder if there is a DNS issue floating around the web (and not just Google DNS either).

 

[Ketchup]

I wonder if comparing a traceroute on the desktop would show where it's getting stuck. Do one on the iPad and you might find it is going a different direction.

I wonder if the iPad is on the wireless carrier and you only think it's on the wifi network.

 

[biostud]

I wonder if comparing a traceroute on the desktop would show where it's getting stuck. Do one on the iPad and you might find it is going a different direction.

I wonder if the iPad is on the wireless carrier and you only think it's on the wifi network.

It's a Wifi only ipad.

 

[John Connor]

Flush the DNS when this happens.

Start | in the search box enter CMD | in the black box enter ipconfig/flushdns.

I would use Opendns. Create an account! When other people can't access a site OpenDNS can.

Referring to the hosts file you should mark it read only. Avira anti-virus locks the host file from edits.

Host file is located in C:system32\drivers\etc

Ccleaner has the ability to flush the DNS cache too. Make sure you select that option.

 

[biostud]

A plot is starting to unfold. So one of the sies that cannot be accessed is java.com. I tried to get my sister to run a online virus scanner that didn't require java, and it fond 15 infected files. She says that she doesn't appear to have a hosts file, but i cant remember if i hav e hidden systems files.

 

[John Connor]

Safe mode | Run Rkill |Malwarebytes.

If that doesn't work I would try Avira rescue system. It's a bootable CD. http://www.avira.com/en/download/product/avira-rescue-system

I'm having trouble downloading, but that may be fixed.

 

[biostud]

Safe mode | Run Rkill |Malwarebytes.

If that doesn't work I would try Avira rescue system. It's a bootable CD. http://www.avira.com/en/download/product/avira-rescue-system

I'm having trouble downloading, but that may be fixed.

So she's done that and in safe mode she can access all the sites, but once she boots normally she can't access the sites. The hosts file is now the standard one from microsofts homepage.

Malwarebytes doesn't find anymore spyware etc.

What's next?

 

[Ketchup]

Superantispyware is a good one.

 

[John Connor]

So she's done that and in safe mode she can access all the sites, but once she boots normally she can't access the sites. The hosts file is now the standard one from microsofts homepage.

Malwarebytes doesn't find anymore spyware etc.

What's next?

Did you try to reset the DNS cache like I mentioned?

 

[biostud]

Did you try to reset the DNS cache like I mentioned?

Flushing the cache + reboot seemed to do the trick. Thanks all for help

 

[John Connor]

Nice to hear. If you get infected again another great tool is Avira rescue CD. What does she have for virus protection?

 

[biostud]

Apparently it only worked for a short time.

I don't know much about how DNS work but to me it seems like there's something in the DNS cache that fvcks up the connection.

 

[biostud]

Nice to hear. If you get infected again another great tool is Avira rescue CD. What does she have for virus protection?

MSE on win7

 

[biostud]

She doesn't get a 'connection-specific DNS suffix' on her wireless connection, when she runs ipconfig.

 

[John Connor]

I would ditch MSE since a virus got past it and install either Avira, Bitdefender or Avast.

I'm wondering if the network card driver should be reinstalled. After uninstalling the driver and reinstalling I would run Ccleaner and do a DNS cache flush again. You may have to try Avira Rescue CD. There still could be malware on there.

 

[debian0001]

try a tracert to the site and see where it is hanging.

 

[biostud]

First I've changed her DNS to norton secure DNS -> flushed DNS -> restart -> no luck

Tried Lan instead of Wifi -> no luck

tried tracert

1: s6.hostlocal.com (207.158.52.56) 0.106ms pmtu 1500
1: 207.158.52.125 (207.158.52.125) 0.511ms
1: 207.158.52.125 (207.158.52.125) 2.752ms
2: vlan127.car1.SanDiego1.Level3.net (4.79.33.229) 0.886ms
3: ae-11-11.car2.SanDiego1.Level3.net (4.69.133.210) 31.071ms asymm 9
4: ae-4-4.ebr2.Dallas1.Level3.net (4.69.133.214) 30.853ms asymm 8
5: ae-61-61.csw1.Dallas1.Level3.net (4.69.151.125) 31.486ms asymm 7
6: ae-2-70.edge5.Dallas3.Level3.net (4.69.145.78) 30.797ms
7: ORACLE-CORP.edge4.Dallas3.Level3.net (4.59.32.6) 31.070ms asymm 8
8: adcq7-swi-7-xe-3-0-1.oracle.com (141.146.0.177) 36.980ms
9: vp-www.java.com (137.254.120.47) 36.842ms reached
Resume: pmtu 1500 hops 9 back 247