Read http://malwaretips.com/blogs/reimageplus-popup-virus/
2. You may have installed some other software from a download site. Many include other apps/virus/trojans/toolbars. It's become a plague. That's why I don't install a lot of new apps today but when I do need something I use Ninite.com since well, here's why.
http://www.howtogeek.com/201354/ninite-is-the-only-safe-place-to-get-windows-freeware/
Somehow this Reimage Popup started appearing on my laptop. I have never installed any Reimage software. I cannot find it to uninstall it.

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