You have a coolwebsearch infection.
Download CWShredder from here & run it. Select the fix button & it will get rid of everything related to CoolWebSearch that is stored in it's database. Close ALL windows, including IE, before running CWShredder.
To help prevent this from happening again, install the patches for the vulnerabilities that this hijacker exploits by going here for your critical updates.
crunchie
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20,095 posts since Feb 2004
Reputation Points: 1,142
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Yahoo may be a cookie problem. Clear all of the old ones & try again. Spywareblaster & guard are two of the better protection tools that you can install.
I use easycleaner from ToniArts for a registry cleaner.
crunchie
Most Valuable Poster
20,095 posts since Feb 2004
Reputation Points: 1,142
Solved Threads: 985
I think from here it is best if you post a HijackThis log.
Download HijackThis from here & unzip it into it's own, permanent folder, (Not a temporary folder or the desktop & not directly on your hard drive). Start HJT & with all browser windows closed, press the scan button. When the scan is finished the scan button will change to save. Save the log to a text file, copy the entire contents of the text file & paste it into the body of your post. DO NOT FIX ANYTHING YET. Most of what is there is harmless & even necessary to the running of your system.
crunchie
Most Valuable Poster
20,095 posts since Feb 2004
Reputation Points: 1,142
Solved Threads: 985
You never mentioned the DSO exploit until your last post either. You should go here & install ALL critical updates required for your system. Get everything on offer for your system & install them.
Also you can download DSO stop from http://www.nsclean.com/dsostop.html
crunchie
Most Valuable Poster
20,095 posts since Feb 2004
Reputation Points: 1,142
Solved Threads: 985