I will pass along something I received from a local computer shop last winter. Get a copy of Malwarebytes at http://www.malwarebytes.org/ They have a free version and the shop loaded it on my computer and cleared my problem.
"Les deux pieds contre la muraille et la tete sous le robinet"
I've used that everyday for just over a year now, (recommended by a guy that services computers) - along with Avast, free version. Do a "complete scan" daily with both.