Toolbars are not always associated with the registry, they may be installed as an addon to your browser. Maybe you could explain the issue you are facing.

Anyway, I did a bit of searching and found that a download manager called ilivid was the one which installed Datamngr for some users. Uninstalling the program could fix the issue for you.

If that doesn't fix it, follow this:
In order to change Searchqu as your homepage please follow the next instructions:

1.Go to Control Panel > Add/Remove Programs > look for windows searchqu toolbar > Uninstall
Do this in Firefox
2.Write in the URL address: "about:config" It'll warn you to be careful. Go in anyway. Search for: "homepage" in the filter and double click "browser.startup.homepage" From here you can change your homepage default settings to a multitude of sites.
source:
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