Yes, I have a big problem - Delta-Homes and FSecure AntiVirus, which cannot find that virus - why not?
"Delta-Homes and FSecure AntiVirus, which cannot find that virus - why not?"
Because it is not a virus but A PUP-Potentially Unwanted Program.
A number of removal Guides here;
In the future I would recommend;
1. Keeping all your software up to date.
2. Only download software from trusted sites.
3. Scan regularly with the free Malwarebytes; it can remove most PUPS; http://www.malwarebytes.org/products/malwarebytes_free/
In order to treat your infection, kindly try following the general removal instructions.
You may also want to use the following tools to scan your system.
Finally if you have a sample available you can submit it to our Lab.
They should be able to tell you more about the detection for the variant of the virus you encounter and how to clean it.