PC infected - DNS error-cannot find server

[Roflcopter66]

Hey again, recently gone to visit my mother and she came to me with her laptop which she claimed was full of viruses and what-not.

Upon using the laptop i tried to install such things as AVG - Adaware and so on. When i searched anything on google, and clicked the link it would just come up "Oops! this link appears to be broken" on google chrome. It states in the corner of the window "DNS error - Cannot find server"
With this in mind i used my USB stick to install the above mentioned anti-virus/anti-malware software.

By scanning them they have since removed the pop ups and other things that were appearing on the laptop; yet still the problem of the "DNS error - cannot find server" remains. It is also (i think) preventing the anti-virus and anti-malware stuff from updating, as none of them can update using the built in update tools.

Laptop is Windows Vista.
I made sure that under Internet options>connections>lan settings it was ticked auto detect settings.
I cleared all cookies and **** like that.

I'm very tired and weary so i'm not sure of what else to provide in terms of information, if you could let me know what you may need to help me i'd much appreciate it. Thanks

 

[Ian]

Can you try running MBAM and see if that comes up with anything?:

http://www.malwarebytes.org/mbam.php

Are all sites broken, or just a few? It could be an infection in the hosts file (http://en.wikipedia.org/wiki/Hosts_file). Can you check to see if there are any extra entries in the following file:

%SystemRoot%\system32\drivers\etc\hosts

 

[Roflcopter66]

I just checked that folder and this is the contents (With ---'s seperating beginning and end)

-------------------------------------------------------------------------------------------------------------------
# Copyright (c) 1993-2009 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

# localhost name resolution is handled within DNS itself.
# 127.0.0.1 localhost
# ::1 localhost

---------------------------------------------------------------------------------------------------------------------

I don't think that's anything out of the ordinary?

It isn't every website, but it appears to be every link from google.
Sometimes, instead of just failing with "DNS server error" i will actually get "re-directed" to a site such as "www.pharmastores.com" - etc.

I'll try running the malwarebytes scan again, it did remove over 150 infections a few days ago, but god knows if they are still there and/or have returned =(

 

[Roflcopter66]

May i also note that whatever is happening is preventing me from updating any of my anti-virus/ad-aware software

 

[muckshifter]

it did remove over 150 infections a few days ago

ask ... http://www.bleepingcomputer.com/ ... to have a look at your pc