Look at Grif Thomas' fixes..specifically bleeping computer...for sure the place to start.
istart123 mysteriously took over the home page of all 3 of my web browsers. You can't close it. It takes over your start page. You can't get rid of it. If you close it's tab, it simply pops another tab back up. It is not a registered program, and there is no program that you can uninstall. I attempted to find istart123 in the Windows 7 registry, but though the name comes up, I was unable to find associated files to delete. Has anyone had this problem?
"BoBrowser" also mysteriously took over Google Chrome. It is also not a registerd program on Windows 7. It takes over the open source Google Chrome and also changes several file associations. I have been able to fix most of the problems via the Windows 7 regristry and a program I downloaded called "Autoruns" by disabling it from starting on boot-up. Anyone having experience with either program would appreciate hearing from you.

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