Yes I try a reboot but unsuccessfully...
I made a "speed scan" because I have some problems with my computer... And when I wanted put in Quaranteen the 9 virus I had this message...
No, avast is installed since a few monts.
(Sorry for my English...)
Even though it was a couple of months ago that you installed, it is still relatively recent and possible to experience conflict if your previous AV wasn't fully removed.
This is why I asked about what your previous AV was, we have links to various removal tools for different AVs to ensure that all remnants are removed, to eliminate that as a possible cause.
So what was your previous AV ?