Home Page isn't an add-on, it's a setting in Forefox's Options.
Try this. Open Firefox then click Firefox, (top left hand corner), then Options, then Options again, (yep, twice), and in the new window with the "General" tab displayed, look at your Home Page entries. If you find more than one, (separated by a comma), manually delete the one you don't want.
I hope that is what you need because your subject title said Yahoo Search Bar, then you go on to talk about Home Page. Two different things I think.
Mark
hi there i have looked in uninstall progs looked in prog files ,i have put a search in for yahoo ,i have made firefox the default homepage in the tools/ options /general tab,and i`ve had a look in add ons but can`t find it , when i open a new tab on firefox it opens as a yahoo page .it came down with 7 zip by accident, could anyone help me get rid of it please thanks

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