This policy setting allows you to add a specific list of search providers to the user's default list of search providers. Normally search providers can be added from third-party toolbars or in Setup. The user can also add a search provider from the provider's website.If you enable this policy setting the user can add and remove search providers but only from the set of search providers specified in the list of policy keys for search providers (found under [HKCU or HKLM\Software\policies\Microsoft\Internet Explorer\SearchScopes]). Note: This list can be created from a custom administrative template file. For information about creating this custom administrative template file see the Internet Explorer documentation on search providers.If you disable or do not configure this policy setting the user can configure their list of search providers unless another policy setting restricts such configuration.
Windows Components\Internet Explorer
At least Internet Explorer 7.0