There is a very good chance that you are seeing the effects of a hijackware
infection!
NB: If you had no anti-virus application installed or the subscription had
expired *when the machine first got infected* and/or your subscription has
since expired and/or the machine's not been kept fully-patched at Windows
Update, don't waste your time with any of the below: Format & reinstall
Windows. A Repair Install will NOT help!
1. See if you can download/run the MSRT manually:
http://www.microsoft.com/security/malwareremove/default.mspx
NB: Run the FULL scan, not the QUICK scan! You may need to download the
MSRT on a non-infected machine, then transfer MRT.EXE to the infected
machine and rename it to SCAN.EXE before running it.
2. [WinXP ONLY!! =>] Run the Windows Live Safety Center's 'Protection' scan
(only!) in Safe Mode with Networking, if need be:
http://onecare.live.com/site/en-us/center/howsafe.htm
3. Run a /thorough/ check for hijackware, including posting requested logs
in an appropriate forum, not here.
Checking for/Help with Hijackware:
..
http://aumha.net/viewtopic.php?f=30&t=4075
..
http://mvps.org/winhelp2002/unwanted.htm
..
http://inetexplorer.mvps.org/tshoot.html
..
http://www.mvps.org/sramesh2k/Malware_Defence.htm
..
http://www.elephantboycomputers.com/page2.html#Removing_Malware
**Chances are you will need to seek expert assistance in
http://spywarehammer.com/simplemachinesforum/index.php?board=10.0,
http://www.spywarewarrior.com/viewforum.php?f=5,
http://www.dslreports.com/forum/cleanup,
http://www.bluetack.co.uk/forums/index.php,
http://aumha.net/viewforum.php?f=30 or other appropriate forums.**
If these procedures look too complex - and there is no shame in admitting
this isn't your cup of tea - take the machine to a local, reputable and
independent (i.e., not BigBoxStoreUSA) computer repair shop.
=====================
Start a free Windows Update support incident request:
https://support.microsoft.com/oas/default.aspx?gprid=6527
Support for Windows Update:
http://support.microsoft.com/gp/wusupport
For home users, no-charge support is available by calling 1-866-PCSAFETY in
the United States and in Canada or by contacting your local Microsoft
subsidiary. There is no-charge for support calls that are associated with
security updates.