These possibly unwanted toolbar issues can be managed easily via using toolbarcop, see: http://windowsxp.mvps.org/toolbarcop.htm

OpenCandy and Ask bar installs could be considered such possibly unwanted browser extensions as they are coming “on the back” of another software install you choose and you did not agree to installing these additionally whether they are actually harmful or not
like there are:

Browser Helper Objects (BHO)

Toolbars

Standard Toolbar buttons

Context menu Extensions

Download managers

Protocol Handlers

Horizontal / Vertical Explorer Bars (side-search bars)

Startup applications originating from RUN registry keys.

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